Contradiction with John 14:27
John 14:27 speaks of peace that Jesus provides, whereas Luke 19:42 refers to the missed opportunity for peace by Jerusalem.
John 14:27: Peace I leave with you, my peace I give unto you: not as the world giveth, give I unto you. Let not your heart be troubled, neither let it be afraid.
Contradiction with Matthew 10:34
Matthew 10:34 mentions Jesus bringing division rather than peace, in contrast to the theme of peace in Luke 19:42.
Matthew 10:34: Think not that I am come to send peace on earth: I came not to send peace, but a sword.