Most languages have different words to describe different kinds of love. In Latin caritas means affection, amor describes romantic love. Like wise in Greek, the language of the Gospel, there are different words for different kinds of love, as the Holy Father discusses in Deus Caritas Est. There is eros, which is passionate love, filius, which is brotherly love, and agape which is the all encompassing love between a husband and wife.
In today's Gospel reading, in the original Greek, different words for love are used. I've replaced the English with the Greek in the following translation. See if you can guess what it means.
When they had finished breakfast, Jesus said to Simon Peter, “Simon, son of John, do you agape me more than these?” He said to him, “Yes, Lord, you know that I filius you.” He said to him, “Feed my lambs.” He then said to him a second time, “Simon, son of John, do you agape me?” He said to him, “Yes, Lord, you know that I filius you.” He said to him, “Tend my sheep.” He said to him the third time, “Simon, son of John, do you filius me?” Peter was distressed that he had said to him a third time, “Do you love me?” and he said to him, “Lord, you know everything; you know that I filius you.” [Jesus] said to him, “Feed my sheep.Now a deacon I know is fond of saying, "Peter, God love him, is not the sharpest pencil in the bunch."
One interpretation of the above passage relates it to Peter's three denials of Christ on the night he was betrayed. Three attestations of love to counterbalance the three denials.
This is also one of the passages that gives Peter the supremacy as the vicar of Christ, giving him authority over the Church.
But we also have to remember when this happened and what had happened just before. This was the third time that Jesus appeared to the Apostles after his resurrection. They knew he had risen, but had not yet been visited by the Holy Spirit.
So Peter, seemingly in forgetfulness of what the Lord had told him, "You will now be fishers of men," decides he is going to go fishing. They catch nothing all night, until the Lord appears on the bank, and as he had before, told Peter where to cast his net.
In this way the disciples recognized it was the Lord.
So after they eat, Jesus asked Peter to attest to his love for him, but not the love of friendship. Jesus ask Peter to profess the complete love which humans only resolve for their spouse, or for God. Peter doesn't get it yet. He answers, attesting his friendship and affection. So Jesus asks again. And again Peter answers. So finally Jesus, knowing Peter is not yet ready, asks him to attest to his friendship and affection. He wants Peter's total love, but he will take his friendship, for the time.
Then Jesus prophesies.
"Amen, amen, I say to you, when you were younger, you used to dress yourself and go where you wanted; but when you grow old, you will stretch out your hands, and someone else will dress you and lead you where you do not want to go.”Which is a description of Peter's death, on the cross.
The first reading today happens after these events. In it Peter and another disciple are called before the Sanhedrin. This time Peter does not flinch. It is after Pentecost, and he is filled with the Holy Spirit.
Eventually Peter will end up in Rome, where he will be hung upside down on a cross, perhaps the best testament to his agape.