Romans 1:9 KJVS
 For God is my witness, whom I serve with my spirit in the gospel of his Son, that without ceasing I make mention of you always in my prayers;
What does this mean?
I serve God with my spirit according to the good news of His son Jess s Christ. Not according to how I feel, what I think, but according to the good news of His son.
Meaning, I serve God based upon what is true in Christ, not my past. What is true in Christ not my feelings. What is true in Christ not my mind.
So if in Christ I am a son, then in spirit I approach God as a son, because it’s true according to the gospel of Jesus.
If in Christ I am loved, then in the spirit I approach God as one who is loved.
If in Christ I am blessed, then to be in spirit means to acknowledge that I am blessed.
Sometimes we have a tendency to serve God in the flesh, which is according to carnal things, and deny the truth of the gospel of Jesus Christ.