The relationship between Peter and the Lord is one of the deepest revealed in all of scripture. We can get a real feeling for the way they interacted over the time they were friends. Now in this final farewell to Peter, Jesus shows how much he loved Peter on a personal as well as divine level. People read all sorts of mystical levels into the words of Peter and Jesus in this passage but on a surface level they are just the words of two friends saying goodbye. For the rest of his life, Peter would keep this moment alive in his heart.
Everything has a natural beginning, middle and end. It is time for Jesus to go and Peter and the apostles are coming to realise this. But Jesus has also promised not to leave them orphans. The Spirit will come. The apostles would not have been sure what this meant but they would have trusted the Lord. We must do the same. We are expected to trust that all shall be well. Jesus shall not let us down.