“It was a great sin.

We see a man, who had followed Christ for three years, and had been forward in professing faith and love towards Him, – a man who had received boundless mercies, and loving-kindness, and been treated by Christ as a familiar friend,-we see this man denying three times that he knows Jesus!- This was bad. – It was sin committed under circumstances of great aggravation.

Peter had been warned plainly of his danger, and had heard the warning.  He had just been receiving the bread and wine at our Lord’s hand, and declaring loudly that though he died with Him, he would not deny Him! – This also was bad.-It was sin committed under apparently small provocation.

Two weak women make the remark that he was with Jesus.  They that stood by say, “Surely thou are one of them.”  No threat seems to have been used.  No violence seems to have been done. But it was enough to overthrow Peter’s faith.  He denies before all.  He denies with an oath.  He curses and swears. – Truly it is a humbling picture!”

“Let us mark this history, and store it up in our minds.  It teaches us plainly that the best of saints are only men, and men encompassed with many infirmities.

A man may be converted to God, have faith, and hope, and love towards Christ, and yet be overtaken in a fault, and have awful falls. It shows us the necessity of humility.

So long as we are in the body we are in danger. The flesh is weak and the devil is active. We must never think, “I cannot fall.”

It points out to us the duty of charity towards erring saints. We must not set down men as graceless reprobates, because they occasionally stumble and err.

We must remember Peter, and “restore them in the spirit of meekness.”

“Brothers, if anyone is caught in any transgression, you who are spiritual should restore him in a spirit of gentleness. Keep watch on yourself, lest you too be tempted.” (Galatians 6:1)

J.C. Ryle, Expository Thoughts on the Gospels, page 376.