1 Chronicles 21:18-20

American Standard Version

¹⁸ Then the angel of Jehovah commanded Gad to say to David, that David should go up, and rear an altar unto Jehovah in the threshing-floor of Ornan the Jebusite. ¹⁹ And David went up at the saying of Gad, which he spake in the name of Jehovah. ²⁰ And Ornan turned back, and saw the angel; and his four sons that were with him hid themselves. Now Ornan was threshing wheat.