I behaved myself as though he had been my friend or brother: I bowed down heavily, as one that mourneth for his mother.

I behaved myself as though it had been my friend or my brother: I bowed down mourning, as one that bewaileth his mother.

As a neighbour and as an own brother, so did I please : as one mourning and sorrowful so was I humbled.

I behaved myself as though he had been a friend, a brother to me; I bowed down in sadness, as one that mourneth for a mother.

As if a friend, as if my brother, I walked habitually, As a mourner for a mother, Mourning I have bowed down.

I behaved myself as though he had been my friend or brother: I bowed down heavily, as one that mourns for his mother.

My behaviour was as if it had been my friend or my brother: I was bent low in grief like one whose mother is dead.

I went about as though it had been my friend or my brother; I bowed down mournful, as one that mourneth for his mother.

I behaved myself - Margin, as in Hebrew: "I walked." The word "walk," in the Scriptures, is often used to denote a course of conduct; the way in which a man lives and acts: Philippians 3:18; Galatians 2:14; 1-Thessalonians 4:12; 2-Thessalonians 3:11. It is not improperly rendered here, "I behaved myself."
As though he had been my friend or brother - Margin, as in Hebrew: "as a friend, as a brother to me." This shows that these persons were not his near "relations," but that they were his intheate friends, or were supposed to be so. He felt and acted toward them as though they had been his nearest relations.
I bowed down heavily - Prof. Alexander renders this, "Squalid I bowed down." The word rendered "I bowed down" refers to the condition of one who is oppressed with grief, or who sinks under it. All have felt this effect of grief, when the head is bowed; when the frame is bent; when one under the pressure throws himself on a couch or on the ground. The word rendered heavily - קדר qodēr - is derived from a word - קדר qâdar - which means to be turbid or foul, as a torrent: Job 6:16; and then, to mourn, or to go about in filthy garments or sackcloth as mourners: Job 5:11; Jeremiah 14:2; Psalm 38:6; Psalm 42:9; and then, to be of a dirty, dusky color, as the skin is that is scorched by the sun: Job 30:28. It is rendered "black" in Jeremiah 4:28; Jeremiah 8:21; 1-Kings 18:45; Jeremiah 14:2; "blackish," Job 6:16; "dark," Joel 2:10; Micah 3:6; Ezekiel 32:7-8; "darkened," Joel 3:15; "mourn and mourning." Job 5:11; Job 30:28; Psalm 38:6; Psalm 42:9; Psalm 43:2; Ezekiel 31:15; and "heavily" only in this place. The "idea" here is that of one appearing in the usual aspect and habiliments of mourning. He had a sad countenance; he had put on the garments that were indicative of grief; and thus he "walked about."
As one that mourneth for his mother - The psalmist here evidently designs to illustrate the depth of his own sorrow by a reference to the deepest kind of grief which we ever experience. The sorrow for a mother is special, and there is no grief which a man feels more deeply or keenly than this. We have but one mother to lose, and thousands of most tender recollections come into the memory when she dies. While she lived we had always one friend to whom we could tell everything - to whom we could communicate all our joys, and of whose sympathy we were certain in all our sorrows, however trivial in their own nature they might be. Whoever might be indifferent to us, whoever might turn away from us in our troubles, whoever might feel that our affairs were not worth regarding, we were sure that she would not be the one; we were always certain that she would feel an interest in whatever concerned us. Even those things which we felt could be scarcely worth a father's attention we could freely communicate to her, for we were sure there was nothing that pertained to us that was too insignificant for her to regard, and we went and freely told all to her. And then, how much has a mother done for us! All the ideas that we have of tenderness, affection, self-denial, patience, and gentleness, are closely connected with the recollection of a mother, for we have, in our early years, seen more of these tilings in her than in perhaps all other persons together. Though, therefore, we weep when a father dies, and though, in the formation of our character, we may have been more indebted to him than to her, yet our grief for him when he dies is different from that which we feel when a mother dies. We, indeed, reverence and honor and love him, but we are conscious of quite a different feeling from that which we have when a mother is removed by death.

Mourneth for his mother - כאבל אם caabel em, as a mourning mother. How expressive is this word!

I behaved myself as though he had been my friend or brother,.... Meaning either Saul or Doeg the Edomite, or some such evil man; somewhat like this he says of Ahithophel, Psalm 41:9; and Arama thinks he is meant here; as Christ of Judas, whom he called friend, when he came to betray him; and who not only ate with him at table of his bread, but was steward of his family, and carried the bag, Matthew 26:50;
I bowed down heavily, as one that mourneth for his mother; or as a mother that mourneth for her son, as Jarchi interprets it, whose affections are very strong; and thus Christ wept over Jerusalem, and had a tender concern for and sympathy with the Jews, his implacable enemies, and wept over them, and prayed for them, Luke 19:41.

behaved--literally, "went on"--denoting his habit.
heavily--or, "squalidly," his sorrowing occasioning neglect of his person. Altogether, his grief was that of one for a dearly loved relative.