If converts become part of Israel and the Jewish people, then why are we required to go by "_______ Ben Avraham"? Wasn't Esau a "Ben Avraham"? Wasn't Ishmael? Does "_____Ben Avraham" mean we are less than fully Children of Israel? Please explain. Thanks!
Abraham was the first convert. He was not born into anything but the idol worshipping traditions of his day. He recognized G-D and served Him. He also brought others to that recognition. He was the first.
Although Issac and Jacob/Israel are very great, they do not have the merit and mission that Abraham had. It is a badge of honor that the righteous convert is called after Abraham, since the convert followed in the same path of service.
It is not possible to measure the great merit of the convert. We can remind ourselves by calling them Ben Avraham.
I hope this helps. :)
When HaShem changed Avram's name to "Avraham" he explained that it stood for "Av hamon goyim," the father of a multitude of nations.
This shows us that every convert is considered the spiritual (not blood) heir of Avraham. Therefore we refer to the convert as "Ben Avraham."
Why not call a convert by the name Ben Yitzchak or Ben Yisroel?
Because Yitzchak and Yisroel did not have the same test as Avraham who needed to break away from his idolatrous family in order to "convert" to Judaism!