'Fall' in the Bible

Of Manasseh also there fell away some to David, when he came with the Philistines against Saul to battle: but they helped them not; for the lords of the Philistines upon advisement sent him away, saying, He will fall away to his master Saul to the jeopardy of our heads.

And David said unto Gad, I am in a great strait: let me fall, I pray, into the hand of Jehovah; for very great are his mercies: and let me not fall into the hand of man.