Jesus told His twelve apostles before He sent them out to proclaim the message of the kingdom to the nation of Israel in Matthew 10:34, "Do not think that I came to bring peace on earth. I did not come to bring peace, but a sword."
Jesus warned them what to expect: not a leisurely vacation, but a life-and-death struggle between good and evil, in which they must be equipped with the weapons He alone provides.
Jesus brings a sword to the human heart:" For the word of God is living and active, sharper than any two-edged sword, piercing to the division of soul and of spirit, of joints and of marrow, and discerning the thoughts and intentions of the heart." -Hebrews 4:12
Jesus brings a sword to human society and human priorities:''"For I have come to set a man against his father, and a daughter against her mother, and a daughter-in-law against her mother-in-law. And a person’s enemies will be those of his own household. Whoever loves Father or Mother more than me is not worthy of me. -Matt.10:37-39
To seek Jesus above every other thing will require fighting a constant battle, not only against sin and the world, but against our self, and the appeal of some of the greatest goods of "life under the sun." It is a battle we can win. In fact, the only way to lose is to stop fighting. The alternative, to try find a way to be both friends with the world and with God, will only make us an enemy of both (James 4:4).
Peace will come when the battle is over.
