go down on knees
go down on (one's) knees
Literally, to kneel down. The priest finished speaking, and the congregation went down on their knees.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
go down on one's knees
to kneel down. The people went down on their knees and prayed. Larry went down on his knees and asked for forgiveness.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.