must needs do something
A set phrase used to emphasize that one absolutely has to do something. You must needs plow this field before the sun sets! He must needs apologize to her, if he ever wants to regain her trust.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
must needs do something1 cannot avoid or help doing something. 2 foolishly insist on doing something.
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