What is a living sacrifice?

Romans 12:1 says,

“I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, [which is] your reasonable service.”

One’s whole person, spirit, soul and body, is metabolized and absorbed into Him by the grace and revelation of Him and His grace. The members of our body will grow into and operate as weapons of righteousness. Adam and Eve could not do this prior to the Fall. The Seed had not yet been born into the world to redeem mankind. In Christ, we now have weapons of righteousness. In Christ, our spirit, soul and body are apprehended and transformed to be like Him. In this process of transformation which Paul describes in verse 2,

“And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what [is] that good, and acceptable, and perfect, will of God.”

We become a perpetual living sacrifice offering Christ and His true righteousness to whosoever is thirsty. The sacrifices brought to the tabernacle are a shadow of this. Those sacrifices were killed and stayed dead. The sacrifices were burnt and consumed. We are burned, drowned, crucified and dead in Him, but are risen to life with Him by His resurrection. In this resurrection we are transformed by the knowledge of Him to be more like Him.

In verse 1, we are presenting our whole being holy. God says, “Be holy as I am holy.” Holiness in the Greek means ‘to set apart for a specific purpose.’ In Christ, we are who we truly are in Him. We are who we truly are in Him. Our lives are hidden in Him. As we grow in His righteous by faith, we grow unto holiness. The purpose of holiness is passively exercised in us by the knowledge of Him. This knowledge of Him blows the wind into our sails and sets the sailboat of our person in motion. The sailboat is only a sailboat when the force and energy of the wind influences the sails. The sailboat is being set apart unto its purpose, but not of itself.

This is acceptable to God because it is the faith of Christ in us by His grace that makes us acceptable before the Father. The knowledge of Christ’s death is the sacrifice in us. It is Christ in us.

Transformation is analogous with the metamorphosis of a caterpillar to a butterfly.
http://www.freedomyou.com/fasting_book/Healing_through_Fasting.htm

“The butterfly is a magnificent example of catabolism (tearing down) and anabolism (building up). During metamorphosis the butterfly’s muscles and organs dissolve into a thick yellow solution. All internal structures are torn down and rebuilt. It emerges from the chrysalis, a new creation. The miraculous aspect of metamorphosis as it occurs while fasting. All substances needed for rebuilding come from within.”

This is an example from nature. Another example could be a tadpole growing into a frog.

We are transforming from death to eternal life. In Christ, we will never die. Our bodies may sleep, but not die. The brethren in the New Testament Church would say a brother or sister would fall asleep. The world would say they died. My mother went to be with the Lord over twenty years ago. Only a momentary sleep compared to eternity. Also, she is not dead. She is in glory with the Lord. She is alive! What hope we have in Christ. He has the keys of death and hell, Revelation 1:18.