Romans 12:1-2 NIV
12 Therefore, I urge you, brothers and sisters, in view of God’s mercy, to offer your bodies as a living sacrifice, holy and pleasing to God—this is your true and proper worship. 2 Do not conform to the pattern of this world, but be transformed by the renewing of your mind. Then you will be able to test and approve what God’s will is—his good, pleasing and perfect will. (more relevant videos below)
In this Romans 12:1-2 verse he deals with the bodies of men, in the next verse with the “mind,” the inner-man, life force of man, which the heart is at the center.
A living sacrifice.— How is the body to become a sacrifice? You must sacrifice your pride of wanting your will be done vs. God’s will be done. You must sacrifice your evil wanting to hide in the darkness of your sins, including your sinful thought life. Whatever your body does (which the center of is your heart. -Proverbs 4:23 NIV), you must examine, compare your behaviors (which includes your thoughts and desires), and repent to the standards of God. -Lamentations 3:40 NIV & 2 Corinthians 13:5 In Luke 9:23, Jesus says, Then he said to them all: “Whoever wants to be my disciple must deny themselves and take up their cross daily and follow me.”
Yet, since you (and all) will fail to sacrifice perfectly, and thus fail to be holy to the perfect standards according to God (which the wages of your failure to hit the mark perfectly is death). Then you must fall at Christ’s feet (including His body — fellow members of The Church) and confess your weaknesses and sins to Christ AND other safe believers. -2 Corinthians 12:8-10 NIV, James 5:16 NIV
What does a perfect sacrifice look like? How perfect are you?
Let thine eye look upon no evil thing, and it hath become a sacrifice; let thy tongue speak nothing filthy, and it hath become an offering; let thy hand do no lawless deed, and it hath become a whole burnt offering. But this is not enough, we must do good works also; let the hand do alms, the mouth bless them that despitefully use us, and the ear find leisure evermore for the hearing of Scripture. For sacrifice can be made only of that which is clean; sacrifice is a firstfruit of other actions. Let us, then, from our hands, and feet, and mouth, and all our other members yield a first-fruit unto God” (St. Chrysostom).
The idea contained in sacrifice is that of dedication. We are to dedicate our bodies to God. But there is to be this distinction between the old Jewish sacrifices and the Christian sacrifice: the one was of dead animals, the other of the living man — his heart & soul. The worshiper must offer, or present, before God, himself, with all his living energies and powers directed consciously to God’s service.
Holy, acceptable unto God.—The qualification sought for in the Jewish sacrifices was that they were to be unblemished, without spot. In like manner the Christian’s sacrifice must be holy and pure in God’s sight, otherwise, it cannot be acceptable to Him.
Reasonable service.—The English phrase is somewhat ambiguous. It might mean “a service demanded by reason.” Such, however, is not the sense of the Greek, but rather “a service of the reason,” i.e., a service rendered by the reason. Just as under the old dispensation the mind expressed its devotion through the ritual of sacrifice, so now under the new dispensation its worship takes the form of a self-dedication; its service consists in holiness of life, authenticity through self-examination and full self-disclosure, along with temperance, soberness, and chastity.
More on Romans 12:1-2 NIV: https://www.biblegateway.com/resources/nivac-sample/Rom.12.1-Rom.12.2
The command to “offer” ourselves to God reminds us of Romans 6, where Paul used this same verb (paristemi) to express the basic response of believers to God’s grace to us in Christ (see 6:13, 16, 19). As new covenant Christians, we no longer offer animal sacrifices; we now offer ourselves as “living sacrifices.” “Living” perhaps has a theological meaning: We offer ourselves as people who have been brought from death to life (see 6:13).
What does “offer your bodies as a living sacrifice” mean? -John Piper
https://www.desiringgod.org/messages/present-your-bodies-as-a-living-sacrifice-to-godhttps://biblehub.com/commentaries/romans/12-1.htm
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