A person can live a God-centered life in the human context, while yet a human being by focusing their thoughts and actions on (by thinking and doing) what God wants of them. The person remains a physical, mortal human being, but his or her reason for being is to serve God according to His standards.
The essence of the matter is the heart of the person, his or her's innermost thoughts and motivations, which lead to action. A God-centered individual, while mortal, concentrates on the spiritual. He or she, if doing God's will, focuses on the heavenly not the earthly:
Do not store up for yourselves treasures on earth, where moth and rust destroy, and where thieves break in and steal.
But store up for yourselves treasures in heaven, where moth and rust do not destroy, and where thieves do not break in and steal.
For where your treasure is, there your heart will be also.
Matthew 6: 19-21 (New International Version (©1984)
Therefore, the God-centered life has an eye to eternity and its rewards, while the individual still lives and toils in the physical realm. The challenge of the God-centered life is to 'overcome' and resist Satan the Devil and all his wiles. This involves trust and faith in God, and letting Him work within you. To "fight the good fight" as the apostle Paul said, and succeeding in that fight, means being God-centered in our thoughts and actions even as we must deal with our own human frailties.
In the end - to those who hold to, believe, and do (act upon) the teachings of Jesus Christ - the God-centered life results in a transformation from mortal into immortality, from corruptible into incorruptible. It is the thoughts and actions, "faith with works", in this physical life that determines our future rewards. Being God-centered means putting God first, ahead of our own human desires.