"Lord, to whom shall we go? You have the words of eternal life." That is Peter's confession as Jesus asks if they want to desert him too. They are words that we read easily, know readily, and yet wrestle with often.
In the context of the passage Jesus turns to the twelve and asks them if they want to leave too because the crowds have reacted with hostility. At the start of ch6 there are well over 5,000 but by the time Jesus asks the twelve there are only the twelve left. Many other disciples have left Jesus along with the crowd. Why? Because they find his words offensive. Peter's confession comes in that context, when everyone else gives up following Jesus Peter and the others continue to follow Jesus because they believe Jesus alone has the words of eternal life, he alone satisfies, he alone gives life meaning, he alone reconnects us with life as we were made to live it - knowing God and enjoying him as our Father.
That has to be our conviction too if we are to follow Jesus and live life listening to his words. Jesus' words clash with out societies words and claims often. The question as we are faced with these two competing claims is which do we believe brings eternal life? As we read the Bible and it clashes with societies morals and norms we face that same question which do I believe brings eternal life?
As those who follow Jesus, who've seen who he is, who know and believe that he is the Holy One of God who gave himself for us because of love we will choose his words. That choice in one sense is often not easy, though it seems like it should be as I write this post, but that has to be our deep settled, deeply held conviction. Jesus words alone bring eternal life.