Bible Verses About Prayer: Falling on the face

They fell flat on their face, and said: O most mighty, the God of the spirits of all flesh, for one man's sin shall thy wrath rage against all?

And he answered: No: but I am prince of the host of the Lord, and now I am come.

And David lifting up his eyes, saw the angel of the Lord standing between heaven and earth, with a drawn sword in his hand, turned against Jerusalem: and both he and the ancients clothed in haircloth, fell down flat on the ground.

And going a little further, he fell upon his face, praying and saying: My Father, if it be possible, let this chalice pass from me. Nevertheless, not as I will but as thou wilt.