With accent marks:
Не рой я́му друго́му, сам в неё попадёшь.
Do not dig a hole for another one, you will fall into it yourself.
This proverb is very old and has its analogues in many languages. It is also found in the text of the Bible.
Its meaning is very clear: do not cause trouble to another one, the circumstances can turn against you.
Other Russian proverbs
Each sandpiper praises its swamp.
Better late than never.
There is no smoke without fire.
You see your friends in the times of trouble.
Not everything that glitters is gold.
Bitter truth is better than sweet lies.
Do not spit in the well - you will need it when thirsty
Water wears away a stone.