by aries » Wed Nov 23, 2011 7:39 pm
I can give you the source for Yishmael mocking Yitchak.
Rashi on Bereshit 22:1 on what was said before HaShem ordered the binding of Yitchak.
Others say after the words of Ishmael. who boasted to Isaac that he had been circumcised when he was thirteen years old without resisting. Isaac replied to him "You think to intimidate me by mention the loss of just one part of the body? If the holy one blessed be he, were to tell me "Sacrifice yourself to Me" I would not refuse. see Sanhedrin 89b; Genesis Rabah 55
Aryeh Shore