And whoever receives one such child in My name receives Me; but whoever causes one of these little ones who believe in Me to stumble, it would be better for him to have a heavy millstone hung around his neck, and to be drowned in the depth of the sea.
While He was still speaking, behold, a crowd came, and the one called Judas, one of the twelve, was preceding them; and he approached Jesus to kiss Him. But Jesus said to him, “Judas, are you betraying the Son of Man with a kiss?”
The Lord knew his betrayer from the very beginning. Yet he called him into the company of the elect. By this he indicated that it will always be this way in the Church, too. No chosen person can nestle down securely, thinking that he could never betray the Lord. We should build, not on our calling, but on the Lord’s grace. Out of the innermost circle of the apostles comes the decisive betrayal. It comes from the one whom the Lord’s whole love was offered, but who did not accept it. Many are called in reality, not just apparently, to the priesthood and to the religious life, and in spite of this become betrayers.
John, Volume 3: The Farewell Discourses, Adrienne Von Speyr.