Parshas V’yechiei: Yaakov says to Yosef ” ????????? ?????????? ??? ?????? ????? .??????? ??? ??????????? ???????? ??????? ????? ????????? ???? ??? ???????” what does this expression mean: “I had not expected to see [even] your face, and behold, God has shown me your children too.”
There is a Gemara in Yevomas(60b) which says when one has immoral relations his face will have a greenish tinge(a sign of sin).So Yaakov was happy to see Yosef’s face was clear.However,that was not enough because there is a gemara in Shabbas(110) that brings down a concoction that if one drinks it his face will be clear of the greenish tinge. The gemara goes on to say that if one drinks it the side effect is sterility.
Now we can fully appreciate Yaakov’s words.It was a double reaction,one that your face is clear,and I see you have children(didn’t drink potion).This means that Yosef was pure of sin.(Chanukas HaTorah)