LuL: It is. Do I ever kid?!?
It’s a Gemarah somewhere so often taken out of context. You’re not my daughter (yet) so I can teach you a piece. Gemarah is discussing problems, pesulim in yichus, like one born from a parent who’s a slave, illegitimate etc. Gemarah then says ?? ????? ???? if one goes around constantly casting a p’esul on others (e.g. he constantly calls others mamzerim), he himself is a posul. Then the gemarah adds Shmuel Says ?????? ????, his p’sul is the same as what he casts on others.
P.S. No, you’re twisting your thumb the wrong way..