As the life of Christ began with a declaration of God’s endowing and imbuing this sin-agitated world with his peace in Jesus (Luke 2:14), in the same way Jesus, the mediator and means of that peace concludes his message to his disciples, before the cross, of peace.
The Christian life is hugely significant in that it involves living in two worlds. The Christian life is unique! It is only in Christ that we, who do live this way, can find true peace (14:27). We find peace while we are in this world, but we do not seek or expect to find peace through the unspiritual means of this world.