Think not that I am come - This is taken from Micah 7:6. Christ did not here mean to say that the object of his coming was to produce discord and contention, for he was the Prince of Peace, Isaiah 9:6; Isaiah 11:6; Luke 2:14; but he means to say that such would be one of the effects of his coming. One part of a family that was opposed to Him would set themselves against those who believed in him. The wickedness of men, and not the religion of the gospel, is the cause of this hostility. It is unnecessary to say that no prophecy has been more strikingly fulfilled; and it will continue to be fulfilled until all unite in obeying his commandments. Then his religion will produce universal peace. Compare the notes at Matthew 10:21.
But a sword - The sword is an instrument of death, and to send a sword is the same as to produce hostility and war.

Think not that I am come to send peace, etc. - The meaning of this difficult passage will be plain, when we consider the import of the word peace, and the expectation of the Jews. I have already had occasion to remark, (Matthew 10:12), that the word שלום shalom, rendered by the Greeks ειρηνη, was used among the Hebrews to express all possible blessings, temporal and spiritual; but especially the former. The expectation of the Jews was, that, when the Messiah should come, all temporal prosperity should be accumulated on the land of Judea; therefore την γην, in this verse, should not be translated the earth, but this land. The import of our Lord's teaching here is this, Do not imagine, as the Jews in general vainly do, that I am come to send forth, (βαλλειν), by forcing out the Roman power, that temporal prosperity which they long for; I am not come for this purpose, but to send forth (βαλλειν) the Roman sword, to cut off a disobedient and rebellious nation, the cup of whose iniquity is already full, and whose crimes cry aloud for speedy vengeance. See also on Luke 12:49 (note). From the time they rejected the Messiah, they were a prey to the most cruel and destructive factions; they employed their time in butchering one another, till the Roman sword was unsheathed against them, and desolated the land.

(8) Think not that I am come to send peace on earth: I came not to send peace, but a sword.
(8) Civil dissentions follow the preaching of the gospel.

Think not ye that I am come to send peace on earth,.... The Jews had a notion of great outward peace and prosperity in the days of the Messiah; which was grounded on several prophecies of the Old Testament, not rightly understood by them; and the disciples of Christ had imbibed the same notion: wherefore our Lord thought fit to let them know the contrary; and that they must not expect outward ease and quiet, and worldly tranquillity would attend their ministry; for though he came to be a peace maker between God and sinners, by the blood of his cross; and was both the author and donor of spiritual peace to his people; and the Gospel he brought with him, and sent them to preach, was the Gospel of peace; which, accompanied with his power, would produce peace in the consciences of men, and be the means of cultivating and maintaining peace among the saints; yet "peace on earth" in a temporal sense, whether in the world in general, or in Judea in particular, must not be expected as the consequence of his coming; so far from it, that he subjoins,
I came, not to send peace, but a sword. By the "sword" may be meant the Gospel, which is the means of dividing and separating the people of Christ from the men of the world, and from their principles and practices, and one relation from another; as also of divisions, discords, and persecutions arising from it: not that it was the intention and design of Christ, in coming into the world, to foment and encourage such things; but this, through the malice and wickedness of men, was eventually the effect and consequence of his coming; see Luke 12:51 where, instead of a "sword", it is "division"; because the sword divides asunder, as does the sword of the Spirit, the word of God.

Think not that I am come to send peace on earth: I came not to send peace, but a sword--strife, discord, conflict; deadly opposition between eternally hostile principles, penetrating into and rending asunder the dearest ties.

Think not that I am come to send peace on earth. Christ has to conquer a peace by overcoming the evil that is in the way of peace. Hence, to preach the gospel of purity and peace always arouses the opposition of the evil doer. Evil has to be put down before peace can prevail. Hence, while the great end that Christ proposes is peace, the immediate result of his coming, and of the preaching of the gospel, was opposition and bloodshed.
I come . . . but a sword. The only sword that Christ or his followers use in the conflict is the Sword of the Spirit, but the persecutor has in every age turned upon them the carnal sword. The sword is sent, because persecutors use it upon the church.