Besetting sin humorous noun phrase
A particular weakness or bad feature
She was so deeply in love with him that she is blind to his besetting sin.
Impatience is my besetting sin.
Used to describe a situation in which people criticize and blame someone else for a fault, mistake or weakness that they also have themselves
The origin of this phrase is not clear.
Used to express something bad is happening again
Here we go again! Lisa has just asked to borrow my new dress.