According to chapter 11, verse 32, “God has committed them all to disobedience, that He might have mercy on all." In previous chapters, we saw that this mercy is expressed through salvation by grace by faith in the Lord Jesus Christ. This salvation consists in the justification of our sin, on our sanctification with the power of the Holy Spirit, and in the glory that will be revealed in us in the future. The rest of Romans determines how we, who have been thus justified by grace, should behave in our daily life towards our brethren in Christ, the society in which we live, our enemies, the authorities and to our weaker brethren.
In view of God's mercy toward us, we must (“I beseech you” ), literally, offer Him the physical part of our being (our bodies: our minds are the subject of the next verse ). Although Paul had the authority of an apostle to command, he pleads here with love (Philemon 8 and 9). An order given with haughtiness is obeyed with resentment, but a request made in love produces joy in its compliance.
The Greek verb translated "to present" is the same word used for the dedication of the first child in the temple (Luke 2:22,23), and was also used with respect to the members of the believer (Chapter 6:13). It denotes an act of free will of the offerer, as he has authority over his own body and decides what to do with it within its limitations, exercising free will.
The presentation of the body to God denotes not only the purpose of preventing the commission of sinful acts with or against our body, but also of glorifying God with it (1 Corinthians 6:20), in its use for good works and with the willingness to go through physical suffering for the glory of God if that were to be required of us. This is the meaning of “present … your members as instruments of righteousness to God." (chapter 6:13).
Herein lies a living sacrifice, holy and pleasing to God:
The reasonable service (in the original Greek it means "worship rendered by the reason (or soul)” is the total dedication of our body in sincere appreciation for what He did for us, thus demonstrating it in a logical and reasonable way. It is logical and reasonable because having the Son of God given His holy body to die for us, the least we can do from now on is to live by and for Him. Isaac Watts put it well in a hymn of praise "Love so amazing, so divine, demands my heart, my life, my all.”
All that is ours includes our knowledge, talents, skills, time, work, possessions, and everything else that we consider "ours." David, the humble shepherd, risked his life and used his skill to beat the giant Goliath who threatened the name of the LORD and His people. He used his musical and poetic talent for writing psalms that we read and many still sing today. Paul gave up a noble and profitable career in the service of the temple to dedicate all he had to the service of the Gospel of Christ (Romans 15:16).
Few of us have the qualities and the opportunities they had, but nevertheless let us use and take advantage of those we have as our own rational service of worship, besides the sacrifice of praise from our lips (Hebrews 13:15) and of our possessions (Hebrews 13:16).
So we should not adapt to the standards, practices and customs of the world around us (it is run by the devil - Ephesians 2:2-3), but change ourselves with the renewal of our minds, discovering what is the good, and perfect will of God, to walk in it.
Our God must be served in spirit and with understanding. He does not impose on us something hard to understand or irrational, but only what is thoroughly enjoyable to the principles of right reason.
There is no "Christian" ritual or religious ceremony in the Gospel of Christ: as the Lord Jesus taught: “the hour is coming, and now is, when the true worshipers will worship the Father in spirit and truth; for the Father is seeking such to worship Him. God is Spirit, and those who worship Him must worship in spirit and truth." (John 4:23-24).
According to the Gospel, worship is to be done in spirit and in truth, that is, according to His Word given to us, the Bible, for this is spiritual. We are all able to provide this service through prayer and hymns and spiritual songs of praise and worship.
The Word of God does not reject the expression of our love for God in holy worship with our body (singing of hymns accompanied by music played by instruments, etc.), but it must be reverent, bringing glory to Him and not the artist, and only if is according to His written word.
In addition, two "ordinances" were introduced to the gospel of Christ: baptism of those who convert to Christ, and the Lord's Supper to which are invited all who are His. They are not rituals, because in themselves they have no physical or spiritual consequences for those who obey them.
God treats us as His adopted children, able to be filled with the Holy Spirit, and therefore we are rational beings. God treats us so, and it is in the same way that we must conduct ourselves in His presence.
1 I beseech you therefore, brethren, by the mercies of God, that you present your bodies a living sacrifice, holy, acceptable to God, which is your reasonable service.
2 And do not be conformed to this world, but be transformed by the renewing of your mind, that you may prove what is that good and acceptable and perfect will of God.
Romans chapter 12, verses 1 and 2