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
Оne can not see the wood for the trees.
If I knew where I would fall, I would lay some straw there.
Being a guest is good, but being at home is better.
A holy place is never empty.
Man does not live thanks to bread alone.
Оne sees the mote in another's eye and ignores the log in his own.
Bitter truth is better than sweet lies.
Water wears away a stone.