Jesus did not choose all the disciples
Jesus is clear that not all of the disciples are clean and not all of them have been chosen. The Scriptures taught that one of them would betray Jesus. Jesus knows that it is Judas who will betray Him. He clearly indicates this later in the passage.
The disciples did not know Judas would betray Jesus
There was absolutely no indication that Judas would betray Jesus. The disciples were so perplexed that they were more prone to question themselves than to point fingers at Judas. No one had the slightest suspicion of Judas.
Jesus shows that He knows the future
Jesus is here demonstrating that He knows and brings about the future. All things happen according to His determinate council and foreknowledge (Acts 2:23.) It is the sovereign choice of Jesus Christ that guides all of human history. He shows this foreknowledge by pointing out to the disciples that Judas would betray Him.
Foreknowledge and predestination proves Jesus’ divinity
Jesus is clear in verse 19 that this foreknowledge proves His divinity. Only God could know and bring about the future like that. Jesus is divine. We must either receive Him or reject Him.
To Reject Jesus is to reject God
It does not matter if we are rejecting Jesus, His teachings, or one of His messengers; to reject Jesus is to reject God. To receive Jesus is to receive God.
Will you follow the Divine Savior, Jesus Christ? Will you receive Him or reject Him?