“The secret things belong to the Lord our God, but the things that are revealed belong to us and to our children forever…” (Deuteronomy 29:29).

As a Bible teacher, I teach only half. In other words, I teach the things God has revealed in his Word—the whole counsel of God—for every believer, Christ-follower, to know. There are other things, though, that other half, which we are not to know.

This is about that second half. In John 13, what don’t we know? (And I’m glad we don’t know.)

We don’t know whom Jesus has chosen.

Jesus says, “I know whom I have chosen” (John 13:18).

God is a sovereign, willing, choosing God with a purpose. If you’re a believer, God knew you, loved you and chose you from before the foundation of the earth. (We’re also free and responsible. I don’t know how to put that all together—yet another thing I don’t know—but this truth, a family secret, is taught in Scripture.)

You can rest assured. You can trust him. God was there when you were born and that was a part of his plan. When you grew up, no matter how bad your background was, he understood it, loved you and oversaw your life.

Jesus says, “I am the good shepherd. I know my own and my own know me” (John 10:14). He then says, “My sheep hear my voice, and I know them, and they follow me” (vs. 27). At this, we can’t help but ask a bit hesitantly, “Uh…Jesus…who are your own?” He answers, “Those who follow me.” “Well, I know that, but who will follow you?” Jesus then answers, “Those who are my own.”

He is saying that we don’t know. I’m glad. If I did know, I would have a tendency to sit and watch, rather than go and love. (As an aside, if you wonder whether or not you belong to him, you’re his. Your question and worry only prove that you belong to him. If you didn’t belong to him, frankly, you wouldn’t care about the things of God or God himself at all.)

We don’t know the future.

Jesus says, “I am telling you this now, before it takes place, that when it does take place you may believe that I am he” (John 13:19).

Do you see what Jesus is doing here? He knows that the disciples will soon discover there’s a betrayer (Judas) in their midst. He is warning them ahead of time lest Peter look at John and say, “Jesus really blew it. I mean, he chose twelve and one of them was a big mistake. If Jesus messed up there, he may not be who he said he was or who we think he is.” Jesus is really saying here, in effect, “I know what I’m doing.”

Often, maybe more often than not, I just don’t know. There is only one God in the universe…and we’re not him.

Jesus knows the future…we don’t. And I’m glad I don’t know.

We all question: Will my family be safe? Will I get cancer? Will my job work out? Will my marriage be happy? Will my spouse ever become a Christian? Will life as we know it end at some point? Will I ever have enough? I don’t know. I’ll tell you something I do know: I know him and he knows.

God doesn’t make any mistakes and you can trust him.

We don’t know people’s thoughts.

We don’t know what comes or goes in the minds and hearts of other people. “The disciples looked at one another, uncertain of whom he spoke” (John 13:22).

Judas was in the disciples’ inner fellowship. Jesus called him. Judas was even entrusted with the money box. Nobody knew, not even the disciples.

It must be horrible to know the hypocrites and liars. It must be horrible for me to know exactly what you think about God and Christ. And how horrible it must be for you to know that about me. I’m glad I can be conned. I’m glad you don’t know what I’m thinking. I’m glad I don’t know what you’re thinking. It’s all right and as it should be because that’s business between you and God. I have no right to ever judge your motivations.

You may be a hypocrite. I may be a hypocrite. I’ll never know and you’ll never know, but God will.

We don’t know the depth of our own sin.

And thank God I don’t know…

We rarely see the depth of our own sin.

In order to get a complete picture here: “When it was evening, he reclined at table with the twelve. And as they were eating, he said, ‘Truly, I say to you, one of you will betray me.’ And they were very sorrowful and began to say to him one after another, ‘Is it I, Lord?’” (Matthew 26:20-22).

The disciples’ response was winsome. Peter didn’t say, “It’s got to be Bartholomew. I mean, he’s been acting weird lately. I’ve seen him out there walking in the fields. I bet he’s the one who’s going to betray Jesus.” Thomas didn’t say, “It’s got to be Peter. You remember Jesus said, ‘Get behind me, Satan.’ It’s got to be Peter. He’s the one who’ll do it.” John didn’t say, “It’s got to be Thomas. He doubts everything that Jesus has to say.” Instead, they asked, “Is it I?”

Let me tell you something about me. There is no sin of which I’m not capable. Let me tell you something about you. There is no sin of which you’re not capable. And when you know that truth in your head and deep down in your very heart, you don’t have to know it in your experience.

We don’t know what God is doing in people’s lives.

“So when he had dipped the morsel, he gave it to Judas, the son of Simon Iscariot. Then after he had taken the morsel, Satan entered into him. Jesus said to him, ‘What you are going to do, do quickly.’ Now no one at the table knew why he said this to him” (John 13:26-28).

Picture the Last Supper. Jesus, as the host, sat in the center. There were two places of honor on either side of him. John sat on Jesus’ right side (John 13:23). As they reclined on couches, they each literally leaned on the breast of the person to their left. And so John was on Jesus’ right, eating with his right hand and leaning on Jesus. Who is sitting on Jesus’ left? Judas.

I can almost see Jesus seeking Judas out before dinner and saying, “Judas, sit with me tonight. Sit here beside me.” So if John leaned on Jesus, Jesus leaned on the person to his left…Judas.

Let me tell you something else. Whenever a host wanted to give particular honor to a guest in the household, right before the meal he would take a piece of bread or meat and dip it in the wine dish, and then give it to the beloved guest. Jesus gave the morsel to Judas.

Jesus was saying in essence, “Judas, don’t do it. It’s not too late to change your mind.” It was an amazing appeal of royal love to the heart of hatred.

I’m constantly amazed at the way God, in secret, deals with other people. So be very careful. Back off…and let God do his thing. God is perfectly capable of convicting, leading and directing in other people’s lives (just as he is in your own).

In C.S. Lewis’ Narnia series, in The Horse and His Boy, one of the children asks Aslan—God, the lion—about another child. This is what Aslan says: “I’m telling you your story, not hers. I tell no one any story but his own.” Remember that.

We don’t know the blackness of night without Christ.

“So, after receiving the morsel of bread, he immediately went out. And it was night” (John 13:30).

The words chosen by the beloved apostle here are not an accident. Given John’s use of the themes of night and darkness, of day and night, he is carefully choosing the addendum. Dark. Foreboding. Frightening. Empty. Night.

I once heard a young man give his testimony. He said, “I didn’t backslide. I just stopped and the light went out.”

One of the reasons I’m faithful (when I am) is that I’ve tasted the dark. I don’t want to go back there. I certainly don’t want to live there. I know what it’s like to look into the darkness alone with no one standing alongside.

Judas turned away from Christ and walked out into the night—into darkness so dark without Christ.

Jesus is here. Once again, he offers a morsel dipped in wine. Once again, he offers a second chance.