8 Tamuz 5775
In our prayers, we refer to Hashem as the "G-d of Avraham" because he was the one who merited to father a holy nation. Then we go further and say "G-d of Yitzchak" lest Yishmael also lay claim to this status and then we go further still and say "G-d of Ya'aqov" lest Eisav lay claim as well. Only the offspring of Avraham, Yitzchak and Ya'aqov are the chosen holy nation. We must be very careful of those who want to take it all back to Avraham Avinu, leaving out Yitzchak and Ya'aqov, so as to bring the children of Yishmael and Eisav into the same family with Bnei Yisrael.
An Abrahamic religion is a religion whose people think Abraham was an important person. The best known Abrahamic religions are Judaism, Christianity and Islam, sometimes added other adherents to this three major Abrahamic religions including: Samaritanism. Druze.
And from various other sources...
Common Roots of Three Abrahamic Faiths: A Foundation for Peaceful Coexistence
...Abraham is a unique figure. His name means "Father of Many Nations." Indeed he is. We trace roots of three different, but related, world religions to...Abraham...Abraham brought the world a new way to see God. This new vision of God evolved over time and became transformed as the three Abrahamic faiths. ...Identifying the common roots of the Abrahamic faiths—while respecting their differences—can also help lay the [foundation] for a durable peace in Middle East.
...Judaism, Christianity and Islam are all Abrahamic faiths
Jewish Interfaith Endeavors: Abrahamic Dialogue
Since September 11, 2001, there has been an increased interest in Muslim religious dialogue among Jews and Christians, leading to what many identify as Abrahamic dialogue. This project employs Abraham as a figure that unites all three faiths. Whether the groups address him in conversation or invoke him only in name, Abraham becomes the symbolic father, the common denominator of monotheism.
This is the basis upon which they are building the One World Religion. Anyone who doesn't go along is to be purged, but instead Hashem will "purge" them!
Beware of any rabbi teaching it or using such terminology.