I cried unto the Lord with my voice
With the voice of his soul, in the language of his mind, mentally, as Moses and Hannah cried unto the Lord when no voice was heard, or articulate sounds expressed, since this prayer was put up to the Lord in the cave where Saul was; though it might have been delivered before he came into it, while he and his men were at the mouth of it, which threw David into this distress; besides the cave was so large as to hold David and his six hundred men without being seen by Saul, and who could discourse together, as David and his men did, without being heard by Saul while he was in it; and so this psalm or prayer might be spoken vocally, though he was there; with my voice unto the Lord did I make, my supplication:
the same thing in other words; "crying" is explained by making "supplication", which is praying to the Lord in an humble manner for grace and mercy, and not pleading merit and worthiness.