Romans 12:1 (NKJV) 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.
“Reasonable service” means that it is only reasonable, or right, that we do this, as God deserves it from us. Paul is saying “Now that you know how God has called you and has saved you, because of his compassion towards you, your only reasonable or logical response is to serve Him or worship Him by presenting your bodies a living sacrifice, holy, acceptable unto God.”
Ephesians 4:1 (NIV) “As a prisoner for the Lord, then, I urge you to live a life worthy of the calling you have received.”
Our reasonable service is imitating Christ.
Philippians 2:1-5 (NIV) “Therefore if you have any encouragement from being united with Christ, if any comfort from his love, if any common sharing in the Spirit, if any tenderness and compassion, 2 then make my joy complete by being like-minded, having the same love, being one in spirit and of one mind. 3 Do nothing out of selfish ambition or vain conceit. Rather, in humility value others above yourselves, 4 not looking to your own interests but each of you to the interests of the others. 5 In your relationships with one another, have the same mindset as Christ Jesus:”
1 Peter 1:15 (NIV) “But just as he who called you is holy, so be holy in all you do”
Paul urges us to re-embrace that role and responsibility: to reflect life that is the logical, rational, reasonable response to so great God, who has revealed himself in and through his Son Jesus Christ, and to so great a salvation, in which God has redeemed and restored us.
Ephesians 4:1-4 (AMP) “So I, the prisoner for the Lord, appeal to you to live a life worthy of the calling to which you have been called [that is, to live a life that exhibits godly character, moral courage, personal integrity, and mature behaviour—a life that expresses gratitude to God for your salvation], 2 with all humility [forsaking self-righteousness], and gentleness [maintaining self-control], with patience, bearing with one another in [unselfish] love. 3 Make every effort to keep the oneness of the Spirit in the bond of peace [each individual working together to make the whole successful].”