In the Old Testament, "peace" was a conventional leave-taking. That meaning is surely appropriate here, but again Jesus' words also have another meaning. The "peace" Jesus gives carries the weight of the Old Testament understanding of God's profound and abiding presence (see Isa 52:7; 54:10; Ezek 37:26-28; Zech 9:10).
This peace is now available in Jesus. This is not the world's peace, nor does it imply that everything shall go smoothly for Jesus' followers, who are instructed not to be afraid....Jesus' peace is a gift for disciples who live in a troubling world.
Pain and loss may always be present with us, but they are never the last word.