וַיָּבֹ֥א דָוִ֖יד עַד־אָרְנָ֑ן וַיַּבֵּ֤ט אָרְנָן֙ וַיַּ֣רְא אֶת־דָּוִ֔יד וַיֵּצֵא֙ מִן־הַגֹּ֔רֶן וַיִּשְׁתַּ֧חוּ לְדָוִ֛יד אַפַּ֖יִם אָֽרְצָה׃
And as David came to Ornan, Ornan looked and saw David, and went out of the threshing-floor, and bowed down to David with his face to the ground.
Read kabbalistic (mystical) interpretation of I Chronicles 21:21: and classical mystical sources.