Thou hast heard... hide not thine... — There is something eminently suggestive in the sequence of the two clauses. The recollection that prayer was answered in the past, prompts its utterance in the present. Historically, the words may point to the intervention of Ebed-melech in Jeremiah 38:7.
At my breathing — i.e., the “sighs” or “sobs” of the mourner.