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 - literally, 'I walked,' or 'went along.'
As though ... or brother. Compare David's lamentation for his enemy, Saul, when slain (2 Samuel 1:17-27).
I bowed down heavily - Hebrew, 'in unsightly appearance;' i:e., with all the outward marks of mourning black and soiled clothing, ashes, unwashed face, etc.