Don't look a gift horse in the mouth

Meaning

Do not be ungrateful for a free gift by trying to evaluate its value or find faults with it. If it is free, just take it and say thank you.

Practical, stern

Used in a sentence

• I know the car is old, but don't look a gift horse in the mouth.
• You got a free ticket to the game, so don't look a gift horse in the mouth.
• My boss gave me a raise, and though it is small, I won't look a gift horse in the mouth.