The word commit has different meaning, and I'll just list some of them:
1.to write something down (commit these ides to paper)
2.to pledge to some position, or to state what you stand on an issue (I asked if he was a participate, but he refused to commit himself.
3. to bind yourself, or to obligate ( commit yourself to a cause)
4. to entrust ( I commit myself to you)
5. to do something, perform an action (to commit murder)
6.to commit to custody (he was committed to prison)