The Pulpit Commentary - 1 Chronicles 12:19
And there fell… of Manasseh to David . Of this use of נָפַל עלא there are many other examples ( 2 Chronicles 15:9 ; Jeremiah 37:14 ; Jeremiah 39:9 ). The phrase does not correspond with our own idiom of "falling to" one's lot, but with that of" falling away" from the service or love of one to another, i.e. deserting. The occasion hero spoken of is described in full in 1 Samuel 29:2-11 . read more
The Pulpit Commentary - 1 Chronicles 12:18
The response of the band, by the mouth of Amasai was worthy of the character of the appeal that David made, both in its heartiness and its high tone. Amasai. Possibly the same with Amasa ( 1 Chronicles 2:17 ), the son of Abigail (David's sister), wife of Jether ( 2 Samuel 17:25 ; 2 Samuel 18:6 ; 2 Samuel 19:13 ; 2 Samuel 20:10 ). Ewald discusses this point ('Genesis Int.,' 2:544). He was made captain of the host by Absalom, afterwards by David, and Joab put an end to his life. ... read more