commit oneself on
commit (oneself) on (something)
To agree to something; to make a commitment to something. I'm sorry, but I can't commit myself on your project because it seems fundamentally flawed.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
commit oneself on something
to agree to something; to promise or pledge to do something. I'm sorry, but I can't commit myself on this matter until I know more details.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.