1 Corinthians 13:2 KJV
And though I have the gift of prophecy, and understand all mysteries, and all knowledge; and though I have all faith, so that I could remove mountains, and have not charity, I am nothing.
That Apostle Paul was a Christian goes without saying. No doubt he was a believer and much used of the Lord. But Paul said that without charity he was nothing. I don't think he meant that in any way other than literally.
Charity is, I believe, a unique sort of love a Christian has for his church. After all, outside our relationship with Christ, the most unique thing about a Christian is this body, which is a church.
To not posses this charity practically negates the Christian's profession of faith. He may be saved but he is nothing like a Christian ought to be.