I agree. Church membership and being spiritual are terms the loose followers of Christ assume. To me though church membership matters for personal growth and support. I am spiritual i assume the position of child of God. God is spirit.
Christ truly is the center. On that point there is no disagreement. He died, He rose, and He is coming again as Judge and King ~Acts 17:31. His sheep hear His voice and follow Him ~John 10:27.
But Scripture also defines what it means to be one of His sheep. It is not a self-assumed position. No one becomes a child of God by calling himself spiritual. “As many as received Him, to them gave He power to become the sons of God, even to them that believe on His name” ~John 1:12. Sonship is given by God, not claimed by man.
You say church membership matters for growth and support. Scripture agrees with the purpose, though it never speaks in modern membership language. Believers are commanded not to forsake assembling together ~Hebrews 10:24–25, to be joined to the body ~1 Corinthians 12:12–27, and to submit to godly oversight ~Hebrews 13:17. That is obedience flowing from salvation, not a substitute for it.
You also say, “I am spiritual.” Scripture warns us to be careful with that language. God is spirit ~John 4:24, yes. But Scripture does not define spirituality as a label we apply to ourselves. It defines it by evidence. “If any man have not the Spirit of Christ, he is none of His” ~Romans 8:9. And where the Spirit dwells, He produces fruit that can be seen ~Galatians 5:22–23.
Knowing the living Christ is not mystical or abstract. It is relational and obedient. “Hereby we do know that we know Him, if we keep His commandments” ~1 John 2:3. That is not legalism. That is Scripture’s own test.
Getting in the Word, praying, and walking rightly before Him are not religious performance. They are the normal life of one who has been made alive by Christ. “If ye love me, keep my commandments” ~John 14:15.
So this comes down to the same question Scripture always asks. Are we hearing His voice and following Him, or are we defining ourselves on our own terms? Christ alone saves. Christ alone gives life. And His Word, not our self-descriptions, tells us whether we are walking with Him.
That is sober truth, and it is loving truth.