Salvation is, from it's beginning to it's finish a matter of choices. One must choose to believe the gospel, then that one must choose to repent according to the plan found in the gospel. He must choose to receive the Holy Spirit. He must choose to walk in the light. These choices are based on what he finds in the truth of the gospel.
From Romans 10: starting with verse 11 and reading through verse 15. "For the scripture saith, whosoever believeth on him shall not be ashamed.
for there is no difference between the Jew and the Greek: for the same Lord over all is rich unto all that call upon Him. For whosoever shall call upon the name of the Lord shall be saved. How then shall they call on Him in whom they have not believed? And how shall they believe in Him of whom they have not heard? And how shall they hear without a preacher? And how shall they preach, except they be sent?
As it is written, How beautiful are the feet of them that preach the gospel of peace, and bring glad tidings of good things."
Serving Christ Jesus is a matter of choice, so belief, faith, trust, and obedience is a matter of choice. Joshua 22: 14 reads: "Now therefore fear the Lord, and serve Him in sincerity and in truth: and put away the gods which your fathers served on the other side of the flood, and in Egypt; and serve ye the Lord. And if it seem evil unto you to serve the Lord, choose you this day whom ye will serve; whether the gods which your fathers served that were on the other side of the flood, or the gods of the Amorites, in whose land ye dwell: But as for me and my house, we will serve the Lord." Choose to serve the Lord if you will, but do it in sincerity and willingly.