With accent marks:
Не руби́ сук, на кото́ром сиди́шь.
Do not chop the branch you sit on
This proverb is addressed to a person who harms himself by his actions.
The English equivalent of this proverb is "To shoot oneself in the foot".
Other Russian proverbs
Who is talking about what, and a lousy one about the bath.
Each sandpiper praises its swamp.
You can't spoil the porridge with butter.
Don’t wave your fists after the fight.
Eggs don't teach the chicken.
If I knew where I would fall, I would lay some straw there.
In a healthy body, healthy mind.
What goes around comes around.