There are no specific instances of direct interaction between George Washington and the Jews that stand out in history (although he certainly interacted with Haym Solomon, who financed the revolution). However, Washington’s letter to the Jews of Newport, RI, (written in response to their salutation to him) has become a well-known statement regarding religious freedom for all:
“...For happily the Government of the United States, which gives to bigotry no sanction, to persecution no assistance, requires only that they who live under its protection, should demean themselves as good citizens....May the Children of the Stock of Abraham, who dwell in this land, continue to merit and enjoy the good will of the other Inhabitants; while every one shall sit under his own vine and fig tree, and there shall be none to make him afraid.”
There are two particular situations in which Abraham Lincoln showed himself to be a friend of the Jews:
1) In 1861, Congress passed a law that all army chaplains had to be ordained Christian ministers. When, shortly thereafter, Rev. (Rabbi) Dr. Arnold Fischer was denied a position, he brought his case before the President. Lincoln immediately acknowledged the injustice of the law. Rather than issue a specific exemption for Rabbi Fischer, Lincoln asked Congress to amend the law -- which it did.
2) In late 1862, General Ulysses S. Grant issued an order expelling all Jews from his theater of action (Kentucky, Tennessee and Mississippi). The cause of the order was Grant’s desire to stop the black market smuggling and selling of cotton, which he blamed on Jews. Cesar Kaskel of Paducah, KY, traveled to Washington and petitioned Lincoln, who immediately canceled Grant’s order of expulsion.