Question

take it upon (oneself) - He's taken it upon himself to point out the mistakes in the emails he receives.  - Why do you take it upon yourself to criticize everything I say or do?

Accepted Answer

to give oneself a job (often that is unnecessary or unappreciated) You can say 'on' instead of 'upon'. E.g. She took it on herself to inform the boss.

Phrasal Verb	take it upon (oneself)
Definition	to give oneself a job (often that is unnecessary or unappreciated)
Examples	- He's taken it upon himself to point out the mistakes in the emails he receives. - Why do you take it upon yourself to criticize everything I say or do?
Note	You can say 'on' instead of 'upon'. E.g. She took it on herself to inform the boss.

Oneself Give Job Unnecessary Unappreciated Point Mistakes Emails