Fellowship is an offshoot of justification. Only a right-standing man can have fellowship.

Man died when he sinned. Not just man, but the whole of mankind. Man became separate from God, and anything separate from God begins to die. So the Bible calls the old man dead, alien, estranged, and enemy.

The job of the Holy Ghost is then to mend broken bridges. Your restoration to God’s family, to koinonia, is by the Spirit.

This reconciliation is to be born again. By the Spirit, you can cry Abba Father. Whatever was the inheritance of that family is now yours. Whatever He does for His children is now yours. Whatever He has to offer is now yours. And this affects everything, including your prayer life.