My Grandma Went to a Fair in England and One Booth Was Aimed Toward Geneology. She Got

my grandma went to a fair in England and one booth was aimed toward geneology. She got a certificate which I quote from:
"The surname Ishmael is of patronymic origin. Patronymic surnames are those names which derive their origin from the personal name of the father of the initial bearer. In this instance, the surname Ishmael is derived from the personal name Ishmael and therefore signifies 'descendant or son of one named Ishmael.' The personal name Ishmael is derived from the Hebrew name Yishmael meaning 'God will hear.' In Bibical history Ishmael was the elder son of Abraham by his wife Hagar and the reputed ancestor of a group of Arabian tribes. his story is related in Genesis 16, 21, and 25. Muslims believe that they are the descendants of Ishmael and that Ishmael was the favored son of Abraham and not Isaac. The Koran states:
'We believe in God, and in that which has been sent down on us and sent down on Abraham, Ishmael, Isaac and Jacob, and the Tribes...'
The name Ishmael has been recorded as a surname in both Germany, where it is regarded as a Jewish name, and in England. In Italy and Dalmatia the name has been recorded Ismaelli and bearers have been included amongst the nobility of both places. One Vincenz de Ismaelli was ennobled in 1824. Probably the most notable bearer of the name Ishmael is the fictional character Ishmael from the nineteenth century American novel Moby Dick.
The Historical Research Centre, dated 26th November 1994."
The above info means that basically at any given point, anyone could have changed their surname to Ishmael, which means that not all Ishmaels are derived from the same line. Further more, because of the Jewish affirmation in England and Germany, it is likely that those of you from the Penn Dutch settelements aren't the same, unless some ancestors decided to change their religion but keep their name.
I still don't know who preceded my ancestor Joseph Ishmael from Guyana, and how he got to Guyana, and where his origins are.
Many people look at my last name and say, "Oh you're Muslim, right?" NO! To explain the story takes so long. I don't know why it is that this particular Ishmael name means more religiously than it does culturally! :-)
Here in Canada we are so multicultural. I've seen the variations of "Ismail" and "Ismael" and admittedly, those people are all Muslim or from the Middle East.