“I beseech you therefore brethren, by the mercies of God, that you present your bodies a living sacrifice, holy, acceptable unto God which is your reasonable service,” Romans 12:1. 

 
Why does Paul refer to this sacrifice as our “reasonable service”? Because as believers in the gospel, Christ is living in us! The impossible becomes possible. Not only that, it becomes entirely reasonable. God has provided the life and power for us to fulfill our responsibility which is this: acknowledge the truth and live out what we believe. 

Listen to what the Apostle Paul tells us in Ephesians 2:4-6: “But God, being rich in mercy, because of the great love with which he loved us, even when we were dead in our trespasses, made us alive together with Christ—by grace you have been saved—and raised us up with him and seated us with him in the heavenly places in Christ Jesus,” (Ephesians 2:4-6 ESV).
This is entirely the work of Christ and we are called to believe and appropriate it through faith.
Note that unbelief can take two forms:
1. A soul can say they do not believe the gospel and make that known by living apart from God.
2. A soul can say he does believe the gospel and live like he does not believe it. 

 
Jesus said, “Not everyone that says unto me “Lord, Lord” shall enter into the kingdom of Heaven, but he that does the will of my Father which is in Heaven,” (Matthew 7:21). 

 
The fact is, we live what we believe. What are you believing?

Jesus poured out His blood for the New Covenant of grace and truth, replacing the Old Covenant letter of the law of Moses. Believers are exclusively under the New Covenant, the last will and testament of Jesus that began after the cross.