What does "walk in the flesh" or "live according to the flesh" mean and how does one "crucify the flesh"?

The Old Testament is Christ hidden. The New Testament is Christ unveiled. We see an explanation of what it means to live according to the flesh in Paul's typology of Hagar and Sarah as the two covenants of Law and Grace in Galatians 4:

21 "Tell me, you who want to be under law, do you not listen to the law? 22 For it is written that Abraham had two sons, one by the bondwoman and one by the free woman. 23 But the son by the bondwoman was born according to the flesh, and the son by the free woman through the promise. 24 This is allegorically speaking, for these women are two covenants: one proceeding from Mount Sinai bearing children who are to be slaves; she is Hagar. 25 Now this Hagar is Mount Sinai in Arabia and corresponds to the present Jerusalem, for she is in slavery with her children. 26 But the Jerusalem above is free; she is our mother. ...

28 And you brethren, like Isaac, are children of promise. 29 But as at that time he who was born according to the flesh persecuted him who was born according to the Spirit, so it is now also."

"walk in the flesh" or “..according to the flesh” simply means “by human effort." It does not mean committing sins anyhow and not caring about God as false doctrine preachers teach. We see an explanation of walking "according to the flesh" in the account of the births of Ishmael and Isaac in verse 23 of Galatians 4 already quoted above-

“23 But he who was of the bondwoman was born according to the flesh, and he of the freewoman through promise, 24 which things are symbolic.”

The NLT version says: “The son of the slave wife was born in a human attempt to bring about the fulfillment of God’s promise. But the son of the freeborn wife was born as God’s own fulfillment of His promise.”

Recall that in the same Galatians 4, Hagar and Sarah are typified as the two covenants of Law and Grace. Sarah (Grace) did not need Hagar (Law) to help her give birth to or raise/train Isaac (the church- you and I in Christ.) Grace is enough. Grace is a person. His name is Jesus Christ. Titus 2:11 says of Him:

"God’s marvelous grace has manifested in person, bringing salvation for everyone."

Ishmael was born according to the flesh aka "in a human attempt to bring about the fulfillment of God’s promise." He was a result of Abraham and Sarah's human attempt to bring to pass God's promise to them that they will bear much fruit. Sarah and Abraham couldn't wait and so decided to hurry God's promise along. Young and fertile Hagar was given to the still-virile Abraham so that they could bear fruit after God had already promised them that Sarah herself would bear the fruit of Isaac through His power.

Isaac did not come until Abraham and Sarah knew 100% that they were POWERLESS to bear fruit. For us today, Christ says in John 15:5-

"I am the vine, you are the branches. He who abides in Me, and I in him, bears much fruit; for without Me you can do nothing.”

See The Passion Translation: “I am the sprouting vine and you’re My branches. As you live in union with Me as your source, fruitfulness will stream from within you—but when you live separated from Me you are powerless.”

Remember how to get separated from Christ - “For if you are trying to make yourselves right with God by keeping the Law you have been cut off from Christ! You have fallen away from God's Grace.” Galatians 5:4.

Many churchgoers are yet to understand the weight and power of the Word of the Almighty about how we get to bear “much fruit" and think that they can at least do something. Just as Abraham (Faith) and Sarah (Grace) did with Hagar (Law,) many are trying to help God to make His word come to pass through human striving at bearing fruit aka keeping the Law or dependence on human effort at obedience. This thought has its root in the belief that God's work cannot succeed without our making it so by some forceful effort on our part. This is exactly what Abraham and Sarah thought as they were engineering Ishmael through Hagar (a picture of the Law.) Until you realise how useless your will-power/human attempt at bearing fruit to God is, all you will produce is the work that is like Ishmael.

Plus God does not recognize such fruit from "human attempt" or having a relationship with Hagar (Law) in order to bear fruit. It is never acceptable to God and like Ishmael, its producers cannot inherit the promise that God made to Abraham. The promise can only be inherited by Grace (typified by Sarah) through Faith (typified by Abraham.) There is no room for Law (typified by Hagar.) Remember what God said to Abraham in Genesis 22:2-

"Then God said, "Take your son, your only son, whom you love--Isaac--and go to the region of Moriah. Sacrifice him there as a burnt offering on a mountain I will show you."

Abraham had two sons at the time, yet God saw Abraham as having an "only son" — Isaac. These things are allegories/typologies that speak of our salvation in Christ according to Galatians 4. Any fruit/righteous work that is borne of human striving at keeping the Law (aka living according to the flesh) is unacceptable to God. Isaiah 64:6 describes such righteousnesses as a menstrual rag in God's sight:

"We are all like one who is unclean, all our so-called righteous acts are like a menstrual rag in Your sight."

Living according to the flesh simply means striving to bear fruit (righteousness, moral excellence, godliness) to God by human striving; it is essentially trying to get right with God by keeping the Law and doing its works. The product of such human effort, even when it seems good, is never pleasing to God and never God's will for we His children in Christ. Even today, the descendants of Ishmael are in conflict with those of Isaac. Those in this position - trying to earn their place in God's kingdom via human attempts aka law-keeping - cannot inherit the blessing that comes through the grace of our Lord Jesus Christ just as Ishmael could not inherit Abraham's legacy.

Isaac on the other hand was an heir because he was born of Sarah, a picture of Grace — God’s underserved, unearned, unmerited favour and not the Law (Hagar.)

The "much fruit" that we bear in Christ the true Vine and God's blessings that we have in Him are not by living according to the flesh (human effort at being righteous.) This is being under Law and not under Grace. Romans 3:20 says: "For no one can ever be made right with God by doing what the law commands. The law simply shows us how sinful we are."

In Christ, we get to bear much fruit by the power of the Holy Spirit in us - the same way Abraham and Sarah produced Isaac - no human striving involved. God gets all the glory. This is why you will never find a true believer boasting about how God gave him a jet because he sowed his car or how he got delivered from satanic oppression because he fasted for 70 days as pastor prescribed. This is akin to Abraham and Sarah glorying in their human attempt that brought forth Ishmael (works) through Hagar (Law) - this a picture of keeping the law to produce works or to get the blessing of God. 

Can you imagine Abraham and Sarah boasting that they gave birth to Isaac because they sowed seed or paid tithe or washed church toilet? Isaac was a gift to Abraham. A child of promise, not that horrid "trade by barter" message that is prevalent in many churches today. For we who are in Christ, God freely gives us all things. FREELY  - See Romans 8:32 - 

"He who did not spare His own Son, but delivered Him up for us all, how shall He not with Him also freely give us all things?"

God's goodness is what leads to repentance, not threats of hellfire and rodents in your finances if you don't pay tithe or keep the Ten Commandments - all efforts in futility in futility that can never make anyone right with God according to Romans 3:20. In Christ, God fills us to overflowing  with His goodness and mercy so much that with what is spilling over, we cannot but be a blessing to those around us. In Him, we gt to love, live a life of moral excellence and even give beyond the lawful regulation of the law tithe, yet not us but Christ in us. 

By Grace, let's not be found following that false doctrine that says:

"Yes we are saved by GRACE but you still have to keep the LAW as a guiding principle for morality and so that you can live a godly life."

This is as foolish as saying that without Hagar (law), Sarah (Grace) cannot raise Isaac (the church.) God's word to us in the same Galatians 4 is; "Cast out the bondwoman and her son." In fact, Hagar (law) would have dealt with Isaac mercilessly and found every fault with him in order to disqualify him from inheriting the promise and better position her own child. Likewise, "the letter (law) kills" all those who try to keep it in a bid to inherit the blessing of Abraham.

Until churchgoers realise how useless will-power/human attempt at bearing the fruit of godliness is, all that will be produced is "righteous" work that is like Ishmael - not recognized by God and cannot inherit the blessing of Abraham. See what God's word says about living a godly life by will-power (walking in the flesh) in Romans 7:18 as was Paul's experience:

For I know that nothing good lives within the flesh of my fallen humanity. The longings to do what is right are within me, but will-power is not enough to accomplish it."

God's word says will-power/human effort is powerless and cannot. But Pride in the arm of flesh (human effort at obedience) that will fail says:

"No, I can. God must be wrong. I still have some good/strength in me. I can keep the law in order to be godly. I can resist the temptation to commit sin by my will-power and sheer determination. I can bear fruit to God by my human effort.”

The Pharisees who persecuted the apostles are perfect examples of people who walked in the flesh. Even after Christ's death and resurrection, they strove with all their might to keep the Law in order to be godly and rejected the finished work of Christ in making the sinner who believes righteous and in saving us from our sins. God's word says of them in Romans 10:

1"My beloved brothers and sisters, the passionate desire of my heart and constant prayer to God is for my fellow Israelites to experience salvation. 2 For I know that although they are deeply devoted to God, they are unenlightened. 3 And since they’ve ignored the righteousness God gives, wanting instead to be acceptable to God because of their own works, they’ve refused to submit to God’s faith-righteousness. 4 For the Christ is the end of the law. And because of Him, God has transferred His perfect righteousness to all who believe."

To "walk in the flesh" or "live according to the flesh” refers to rejection of God's gift of righteousness through Christ and dependence on human effort at bearing fruit to God or being godly aka "be like God." This is the default mode of all mankind thanks to the old/sinner nature that Adam passed on to all of his edscendants-

"By one man's disobedience many were made sinners, so also by one man's disobedience many will be made righteous." Romans 5:19.

In Christ, we no longer have the old/sinful nature. We are a new creation in Christ with His Righteousness nature. In Him, God sees us as righteous, not because we kept the Law or tried to be godly (be like God as Adam and Eve did...they died) but through the blood of Jesus: see Romans 5:9-

And there is still much more to say of His unfailing love for us! For through the blood of Jesus we have heard the powerful declaration, “You are now righteous in My sight.” And because of the sacrifice of Jesus, you will never experience the wrath of God."

People "who walk in the flesh" might profess Christ but they still rely on their non-existent human effort at keeping the law in order to remain righteous in God's sight and be in God's good books. Their preaching usually goes along the lines of:

"Yes we are saved by Grace (Sarah) through Faith (Abraham) but we still have to keep the Law (Hagar) as a guiding principle for morality, in order to maintain godliness and so that we don't miss heaven."

Such are not a new creation. They still have the old (sin) nature that Adam passed to his descendants and trust in their non-existent will-power to keep the law. The very law that such are trying so hard to keep arouses sinful passions in them and produces a harvest of sinful deeds aka "works of the flesh" that lead to death; see Romans 7:5-

“For when we were in the realm of the flesh, the sinful passions aroused by the law were at work in us, so that we bore fruit for death.”

See the New Living Translation: "When we were controlled by our old nature, sinful desires were at work within us, and the law aroused these evil desires that produced a harvest of sinful deeds, resulting in death."

In essence, "walking in the flesh" means trying to keep the Law in order to be godly or bear fruit to God. The one who is walking in the flesh cannot but produce "works of the flesh" like lust and such because the law that such are trying to keep in order to be godly was designed to increase sin: Romans 5:20-

"The law was given so that sin would increase..."

The religious "holy holy" Pharisees are perfect examples of living according to the flesh. With all of their law-keeping and great show of tithing, they could not cast the first stone at the sinner woman that they condemned. They were always scheming against Christ who is Grace-personified (See Titus 2:11 below. GRACE is a Person. His name is Jesus Christ.)

The Pharisees' counterparts in many places of worship today whose teaching is nothing but a watered-down version of Judaism with "in Jesus name" attached to prayer points also persecute children of Grace (Jesus Christ Himself!) But with all of their claims of being holy and being able to keep the Ten Commandments, horrid scandals, selfishness and greed follow them everywhere. Such usually run under the canopy of Grace when they are caught in the act with comments like "I am only human." What they do not know is that the Law that they are trying to keep and are force-feeding their congregation aka human attempt at living a godly life is why sin has dominion in their lives:

"For sin shall not have dominion over you for you are not under Law but under Grace." Romans 6:14.

If you confess that you cannot drive, Satan will not ask for you to test your driving skills aka sift you like wheat based on your boast as he did Peter who boasted in his will-power to keep the 8th Commandment - "You shall not bear false witness." He knew 100% that he would not, just as many of us deceive ourselves by thinking that there are some sins that are beneath us. Under Grace, surrendered to Christ and humbling yourself under the mighty hand of God, sin shall not have dominion over you.

Ephesians 2:8-9 says:

"For it is by grace [God’s remarkable compassion and favor drawing you to Christ] that you have been saved [actually delivered from judgment and given eternal life] through faith. And this [salvation] is not of yourselves [not through your own effort], but it is the [undeserved, gracious] gift of God; 9 not as a result of [your] works [nor your attempts to keep the Law], so that no one will [be able to] boast or take credit in any way [for his salvation]."

"Salvation" here is not just being saved to go to heaven; it is also deliverance from the molestation of enemies and redemption from all earthly ills. It is being saved from the power, pleasure and penalty of sin. It is being saved from sins to bear every fruit of the Spirit. The word used in the original Greek text of the New Testament is Swthria (pronounced soteria) and it encompasses all these meanings.

Isaac was a fruit of pure Grace (Sarah) through Faith (Abraham.) Abraham and Sarah were 100% unable to bear fruit and they knew it. Their human attempt at getting a child through Hagar also backfired - Ishmael had no issues with Isaac until the day Isaac was weaned. He started to mock Isaac when Isaac was weaned: Genesis 21-

8"The child grew and was weaned, and Abraham made a great feast on the day that Isaac was weaned. 9 Now Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, mocking. 10 Therefore she said to Abraham, “Drive out this maid and her son, for the son of this maid shall not be an heir with my son Isaac.”

The same thing is happening in many places of worship today! See Galatians 4:

28 And you brethren, like Isaac, are children of promise. 29 But as at that time he who was born according to the flesh persecuted him who was born according to the Spirit, so it is now also."

Pastors and leaders who preach human effort at keeping the law in order to bear the fruit of godliness (children of Hagar) have no problem with churchgoers.... until these churchgoers see and believe Grace and claim their birthright as born-again Christians:

GOD'S GIFT OF RIGHTEOUSNESS TO US IN CHRIST.

Scoffing from those who think they can keep the Law begins after you put your trust in Christ for righteousness and strength, proclaim Him as "The Lord our Righteousness" and are no longer depending on your will-power/human effort at keeping the Law and doing its works (e.g fasting for deliverance from Satanic oppression and sowing seed to get your own Father to bless you) to make you right with God. All these blessings are our inheritance in Christ that we receive by speaking what we believe.

Also, Hagar developed major "housegirl turned mistress" attitude towards Sarah after Hagar (Law) was introduced to Grace and Faith: See Genesis 16-

"Now Sarai, Abram’s wife, had borne him no children. But she had an Egyptian slave named Hagar; 2 so she said to Abram, “The Lord has kept me from having children. Go, sleep with my slave; perhaps I can build a family through her.” Abram agreed to what Sarai said. 3 So after Abram had been living in Canaan ten years, Sarai his wife took her Egyptian slave Hagar and gave her to her husband to be his wife. 4 He slept with Hagar, and she conceived. When she knew she was pregnant, she began to despise her mistress. 5 Then Sarai said to Abram, “You are responsible for the wrong I am suffering. I put my slave in your arms, and now that she knows she is pregnant, she despises me. May the Lord judge between you and me.”

See Sarah whom the Lord had promised that she would be a mother of nations complaining that the Lord kept her from having children! Believer, whatever area of your life it is that you are looking to God for fruit -health, finances, employment, children, how to manage your kids' plenty homework and 18 subjects in JSS 1 - by Grace, keep on looking to JESUS. Romans 8:32 says God gives us all things freely with Christ.

Remember Abraham slept with Sarah even in their dead reproductive state so this is not an issue of leaving your kids' schoolwork unattended, dumping your CV or waiting for billions to magically appear in your bedroom. See Sarah's words when the Lord appeared to Abraham and the prophecy that Isaac would be born within a year was given in Genesis 18:

10 One of them said, “Nine months from now I will come back, and your wife Sarah will have a son.”

Sarah was behind him, at the door of the tent, listening. 11 Abraham and Sarah were very old, and Sarah had stopped having her monthly periods. 12 So Sarah laughed to herself and said, “Now that I am old and worn out, can I still enjoy sex? And besides, my husband is old too.”

The Lord Himself will strengthen and lead you on the right path in your area of need, just as He made Abraham and Sarah able to copulate and bear fruit despite their deadness in those areas.

By God's grace, never trust yourself or your puny will-power. Never allow any wielder of the Law who professes to be for Christ (under Grace) to bamboozle you into doing things like sowing your car so that our heavenly Father who gives us all things freely with Christ can give you a jet. This "trade by barter" arrangement is not of Christ! If you follow this way, you may see results and be able to boast in your will-power like Hagar but only the fruit of Ishmael can come from this union with the Law. God does not recognize it and it will delay your Isaac.

Sarah was barren even as a young woman and Abraham's reproductive organs were dead when Isaac was conceived so they had nothing to boast about. This is why a true believer can never say things like "I sowed my car and God gave me a jet." For all the fruits of the Spirit that we get to bear by virtue of our being a part of Christ the True Vine, God gets all the glory.

Never trust yourself (arm of flesh.) Trust in Christ. Remember 2 Corinthians 3:6-

"He has qualified us [making us sufficient] as ministers of a new covenant [of salvation through Christ], not of the letter [of a written code] but of the Spirit; for the letter [of the Law] kills [by revealing sin and demanding obedience], but the Spirit gives life."

With the Spirit of the Lord, it is neither by might nor by power.

Right believing always produces right living