I was googling randomly and entered "thobbni" (ASCII Maltese for "you love me") and came across a sermon, and went over it to see how much I would understand.
After the reading (John 21:1-19) came the sermon, and including this bit:
Fit-traduzzjoni tal-Malti m'hemmx differenza bejn il-verbi li Gesu' juza' fil-mistoqsijiet tieghu u fir-risposti li jaghti Pietru. Il-Malti juza' dejjem il-verb "habb". Fil-Grieg hemm zewg verbi ghall-verb taghna "habb". Dawn huma "fileo" u "agapao". Il-verb "fileo" ifisser tkun habib ta' xi hadd—din hija l-imhabba naturali ta' bejn zewgt ihbieb jew ta' bejn omm u binha. Filwaqt li l-verb "agapao" ifisser thobb billi tkun lest li taghti hajtek. Liema wahda minn dawn it-tnejn juza Gesu' fil-mistoqsija li jaghmel lil Pietru: "Thobbni int aktar minn dawn?"
Fl-ewwel mistoqsija jghidlu: "Xmun bin Gona, thobbni int (agapas se) aktar minn dawn? Gesu' jistaqsi lil Pietru: "Xmun bin Gwanni, inti thobbni kif inhobbok jien, billi lest li naghti hajti ghalik? Lest li taghti hajtek ghalija?" Pietru, b'umilta kbira fuqu, jirrispondi: "Mulej int taf li nhobbok (filo se)!" Fi kliem iehor Pietru jghid lil Gesu': "Mulej, int taf li nixtieq inkun habib tieghek!"[...]
Fit-tieni domanda ghandna ripetizzjoni tal-ewwel wahda. Gesu' jistaqsi lil Pietru: "Agapas me", u Pietru jirrispondi "Filo se".
Fl-ahhar domanda ghandna xi haga partikolari. Gesu' ma jistaqsix il Pietru jekk hux lest li jaghti hajtu ghalih, izda jistaqsih jekk iridx ikun habib tieghu. Gesu' juza l-istess verb li juza Pietru: "Xmun bin Gwanni, thobbni (filieis me)?".
which, if I understand correctly, means something along these lines:
In the Maltese translation, there is no difference between the verbs which Jesus uses in his questions and in the responses which Peter gives. Maltese always uses the verb "to love". In the Greek, there are two verbs corresponding to our verb "to love"; they are "fileo" and "agapao". The verb "fileo" means to be a friend of someone—this is the natural love between two friends or between a mother and her son. On the other hand, the verb "agapao" means to love in such a way that you are ready to give up your life. Which one of these two does Jesus use in the question which he poses to Peter: "Do you love me more than these?"
In the first question, he says to him, "Simon son of John, do you love me (agapas me) more than these?" Jesus asks Peter: "Simon son of John, do you love me the way I love you, who am ready to give up my life for you? Are you ready to give up your life for me?" Peter, with great humility, responds: "Lord, you know that I love you (filo se)!" In other words, Peter says to Jesus: "Lord, you know that I want to be your friend!" [...]
In the second question, we have a repetition of the first one. Jesus asks Peter, "Agapas me," and Peter responds, "Filo se".
In the last question, we have something special. Jesus doesn't ask Peter whether he is ready to give up his life for him, but asks him whether he wants to be his friend. Jesus uses the same verb that Peter does: "Simon son of John, do you love me (fileis me)?".
That's a difference I had never noticed, so I had a look to see whether I could find a Greek New Testament. I suspected that Wikisouce might have one, and found this, and indeed it has the alternation between φιλώ and αγαπώ that was mentioned in the text.
Whether the interpretation given in the sermon is correct, I don't know, but it's still interesting to see that there were two different verbs involved, and that Jesus used both of them (αγαπώ in the first two questions and φιλώ in the last one) while Peter uses only φιλώ in all three of his answers.
I don't think it was ever pointed out to me (say, in Sunday School or Seminary) that Jesus didn't repeat precisely the same question three times, but that in the third question, he used a different word, namely the one Peter used. (I suppose that also means that the bit "ελυπήθη ο Πέτρος ότι είπεν αυτώ το τρίτον· φιλείς με" isn't quite accurate since it wasn't the third time that Jesus had asked him whether he "φιλεί" him.)
(Also, randomly: I was surprised how much I understood, at least of the passages I quoted; several other bits of the sermon had too many words I couldn't understand. With the reading, of course, it helped that I knew the story so it's easier to get the gist even if you don't know, for example, the word for "net" or "hand sth. to so.".)