Muhammad, the Talmud does not give the age of consent as 3. You read it on Stormfront.
Oops! It's three years and a day. My mistake. I made sure that I'd read it in the Talmud myself, of course, before posting it. That's something you may want to start doing, Mordechai.
Rabbi Joseph said: Come and hear! A maiden aged three years and a day may be acquired in marriage by coition, and if her deceased husband's brother cohabits with her, she becomes his. - Babylonian Talmud, Tractate Sanhedrin, Folio 55b.
Rabina said: It is therefore to be concluded that a heathen girl [communicates defilement] from the age of three years and one day, for inasmuch as she is then capable of the sexual act she likewise defiles by a flux. - Babylonian Talmud, Tractate 'Abodah Zarah, Folio 37a.
Babylonian Talmud: Sanhedrin 55
Babylonian Talmud: 'Abodah Zarah 37
This is from the Rabbi Dr. Isidore Epstein's translation.