וַיָּ֣שָׁב אָרְנָ֗ן וַיַּרְא֙ אֶת־הַמַּלְאָ֔ךְ וְאַרְבַּ֧עַת בָּנָ֛יו עִמּ֖וֹ מִֽתְחַבְּאִ֑ים וְאָרְנָ֖ן דָּ֥שׁ חִטִּֽים׃
And Ornan turned back, and saw the angel; and his four sons that were with him hid themselves. Now Ornan was threshing wheat.
Read Midrashic interpretations of I Chronicles 21:20: rabbinic exegesis from Bereshit Rabbah, Shemot Rabbah and classical Midrash sources, free.