John 21:17

But to him who had uttered a threefold denial, opportunity is given of a threefold confession, although Peter at first resented the reiterated inquiry: Ἐλυπήθη … He was grieved because doubt was implied, and he knew he had given cause for doubt. His reply is therefore more earnest than before, Κύριε … φιλῶ σε. He is so conscious of deep and abiding love that he can appeal to the Lord's omniscience. The σὺ πάντα οἶδας [or πάντα σὺ οἶδας with recent editors] reflects a strong light on the belief which had sprung up in the disciples from their observation of our Lord. And again he is commissioned, or commanded to manifest his love in the feeding of Christ's sheep. The one qualification for this is love to Christ. It is not for want of time no other questions are asked. There was time to put this one question three times over; and it was put because love is the one essential for the ministry to which Peter and the rest are called.