Simon Peter said to Him, "Lord, where are You going?"
"Where I am going, you cannot follow Me now, but you'll follow Me afterward."
"Lord, why can't I follow You now? I'll die for Your sake."
"Will you? You'll without fail deny Me three times before dawn." (John 13:36-38)
This is where the chapter breaks. I think this is where most of us would break it, too. Peter, you failure. Your failure is why you can't follow the Lord now.
But Jesus was still talking. In light of this devastating news to Peter, Jesus says, "Don't let your heart be troubled."
WHAT?! How could he not let his heart be troubled? Peter would rather die for His sake and go with Him than be left behind, but Jesus tells him that in fact, he's going to fail Him utterly three times before dawn.
"Don't let your heart be troubled; you believe in God, believe also in Me."
Peter's failure did not trouble Jesus, and He asked Peter to not be troubled by it either. God's love, and His work on Peter's behalf were sufficient to provide for Peter's failure. Trust Me, Peter -- I won't let you go. Your failure can't nullify My work.
"In My Father's house are many mansions; if it were not so, I would have told you. I go to prepare a place for you. And if I go and prepare a place for you, I will come again and receive you to Myself; that where I am, there you may be also."
Although you will fail multiple times, Peter, and although you can't follow Me, I have you in mind. I will complete what you will always fail to complete. I'm coming back for you. You'll be with Me, but not by your efforts. I will do it for you. You just believe Me.
Jesus spoke of Peter's coming failure as inevitable. Peter's failure was inevitable because Peter was a failure.
I am a failure. You are a failure. It is inevitable that failures will fail. But Jesus never fails. And His words to His friend, His wannabe follower, His disciple, His beloved failure, on the very eve of his failure are, "Believe in Me."
If God is for us, who can be against us? We are more than conquerors through Him who loves us.