Jesus talking in John 21:22
It is the Spirit which gives life. The flesh will not help you. The things which I have told you are spiritual and are life. But some of you will not believe me. - For Jesus knew from the beginning which of his followers did not trust him and who was the man who would betray him. Then he added, "This is why I said to you, 'No one can come to me unless my Father puts it into his heart to come.'"