Jesus has some rather harsh words concerning his mission and for those who follow him. This is not a comforting passage. As he begins this passage he reminds his disciples that he came to bring fire to the earth. Fire is symbolic of purification. Silver was refined and purified in Malachi.
Fire is also a symbol of sacrifice.
The laws in Leviticus depict God s favorable view of sacrifices being burned on the altar. Jesus has come to purify the world and indeed to offer himself as the sacrifice that is pleasing to the Father. In this passage and with these words, Jesus understands what is before him. Perhaps even expressing a bit of anxiety and stress as he mentions that his mission is not about peace, it is about the Kingdom of heaven and is directed to those who will believe. Jesus would not depart from his mission.