I am for peace - Margin, "A man of peace." Literally, "I (am) peace." It is my nature. I desire to live in peace. I strive to do so. I do nothing to provoke a quarrel. I would do anything which would be right to pacify others. I would make any sacrifices, yield to any, demands, consent to any arrangements which would promise peace.
But when I speak - When I say anything on the subject, when I propose any new arrangements, when I suggest any changes, when I give utterance to my painful feelings, and express a desire to live differently - they will listen to nothing; they will be satisfied with nothing.
They are for war - For discord, variance, strife. All my efforts to live in peace are vain. They are determined to quarrel, and I cannot prevent it.
(a) A man in such a case should separate from such a person, if possible, as the only way of peace.
(b) If his position and relations are such that that cannot be done, then he should be careful that he does nothing himself to irritate and to keep up the strife.
(c) If all that he does or can do for peace is vain, and if his relations and position are such that he cannot separate, then he should bear it patiently - as coming from God, and as the discipline of his life. God has many ways of testing the patience and faith of his people, and there are few things which will do so more effectually than this; few situations where piety will shine more beautifully than in such a trial;
(d) He who is thus tried should look with the more earnestness of desire to another world. There is a world of peace; and the peace of heaven will be all the more grateful and blessed when we go up to it from such a scene of conflict and war.

I am for peace - We love to be quiet and peaceable; but they are continually engaged in excursions of rapine and plunder. It is evident that the psalmist refers to a people like the Scenitae or wandering Arabs, who live constantly in tents, and subsist by robbery; plundering and carrying away all that they can seize. The poor captives wished them to cultivate the arts of peace, and live quietly; but they would hear of nothing but their old manner of life.

I [am for] (g) peace: but when I speak, they [are] for war.
(g) He declares what he means by Meshech and Kedar, that is, the Israelites who had degenerated from their godly fathers, and hated and contended against the faithful.

I am for peace,.... Am wholly peace; a man of peace, as Aben Ezra; of a peaceable disposition, devoted to peace; love it, seek and pursue it, as every good man does, who is called to it, and in whose heart it rules: such follow peace with all men, and the things which make for it; and, as much as in them lies, endeavour to live peaceably with all;
but when I speak, they are for war; make a motion for peace, and propose the terms of it, they declare against it, and for war: or when he spoke of the things of God, and of his experience of them, of the word of God, and of the truths of it, and of what he believed, Psalm 116:10; and especially when he gave good counsel and advice to them, and reproved them for their sins, they could not bear it; but hated him for it, and proclaimed war against him; and could not behave peaceably to him in any degree, but became his avowed, sworn, and implacable enemies. The Targum is,
"when I prayed;''
either prayed to God, that they did not like; or prayed for peace with them, that they would not grant; but became more imbittered against him.