No, he was not considered illegal at the time he was born.
People have to put away the customs and laws of TODAY .. and look at what the customs and laws were during the time of the births of Ishmael and Isaac.
And .. we’re talking about Jewish Law .. which was not necessarily the laws of other groups of people.
As I stated clearly in 115, the laws at the time of Ishmael’s birth were totally different from what we have today. Clearly, any slave was the “property” of the family. Therefore, though Ishmael was not CONSIDERED the “first born” (because he was not born of Sarah who was the wife of Abraham - by Covenant Marriage); and this is why Isaac was the child of God’s promise .. and Ishmael could not be the child of promise because his mother was not a part of a Covenant marriage to Abraham. It’s really that simple.
However, Hagar caused her own problems. She did not understand her place “in the family” (primarily because she was not Jewish; she was Egyptian). Ishmael was still a child of Abraham, and he would have had high standing in the family, but he was NOT entitled to the inheritance.
So, you cannot judge Ishmael’s place by the LAWS OF TODAY; that is why you’re trying to say Ishmael was “illegal”. By today’s standard, Ishmael would have been an “illegitimate” child; but during Abraham’s time .. the laws were totally different.
I have for the last few months, been attending a Bible school course. Just got down with this quarter for Thanksgiving. Did first on the book of Exodus. Genesis is next. Had one teacher for the Exodus classes. Another one is coming in for the rest of this term. Was going to throw that possible question about if Ishmael was legit or not. May still do it, but have to go beyond what we do know today and go into the backround of the Bible period.