Surah 2. Al-Baqara, Ayah 133

I.e. "In the religious traditions to which you adhere". It is to be noted that the conjunction am which stands at the beginning of this sentence is not always used in the interrogative sense ("is it that...?"): sometimes - and especially when it is syntactically unconnected with the preceding sentence, as in this case - it is an equivalent of bal ("rather", or "nay, but"), and has no interrogative connotation.

In classical Arabic, as in ancient Hebrew usage, the term ab ("father") was applied not only to the direct male parent but also to grandfathers and even more distant ancestors, as well as to paternal uncles: which explains why Ishmael, who was Jacob's uncle, is mentioned in this context. Since he was the first-born of Abraham’s sons, his name precedes that of Isaac.

The whole of the Children of Israel are called to witness one of their slogans, that they worshipped "the God of their fathers." The idea in their minds got narrowed down to that of a tribal God. But they are reminded that their ancestors had the principle of Islam in them - the worship of the One True and Universal God. The death-bed scene is described in Jewish tradition.

"Fathers" means ancestors, and include uncles, grand-uncles, as well as direct ascendants.