"A believer must put his faith to work. Total involvement in the work of the Lord by all members of the church is one of the great needs of our day. This is true not only for the progress of the work of the church, but especially for the spiritual growth and development of each member. Believers are called not only to salvation, but also to service.
We are not only saints, but servants. Our vocation is service, and there is no genuine satisfaction in life without fulfilling this vocation. Retirement from Christian service is never suggested in the Bible. God has a program of joyful service for every believer wherein he can find joy and contentment, exercising his special ability for the Lord."
-Stanley Ellisen, "The Book of Romans," Progressive Bible Studies (Portland, Oregon, 1975), 180.
But “reasonable,” here, probably describes the area in which we perform this sacrificial, worshipful “ministry” of offering ourselves to God. In other words, we do so in the sphere of reason, rather than in the real, literal sense. The old priests performed a literal, physical, tangible ministry. But ours is a rational, spiritual ministry, in the mind and soul instead of with literal tabernacles and altars and animals.
-Robert E. Picirilli, The Book of Romans, Clear Study Series (Nashville, TN: Randall House Publications, 1975), 241.
The soul ("life") is comprised of :
1) Mind- What I know, believe, & affirm
2) Will- Actions based upon my convictions
3) Emotions- How I feel about a subject