What religion did Abraham belong to before he founded Abrahamism?
What religion did Moses belong to before he founded Judaism?
What religion did Muhammad belong to before he founded Islam?
Peace be on you.
Prophet Abraham:
"And verily of his [Noah's] party was Abraham." (Holy Quran, Chapter 37: Verse 84)
And Noah believed in Allah: "We sent Noah to his people and he said, 'O my people, worship Allah, you have no other God but Him........." (ch 7: V 60)
Thus Prophet Abraham (on whom be peace ) believed in One God before he was commissioned.
Holy Quran records his debates with idol worshipers. Plz check in alislam.org/quran
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Prophet Moses:
Moses was from progeny of Noah:
[6:85]"..........and Noah did We guide aright aforetime, and of his progeny, David and Solomon and Job and Joseph and Moses and Aaron......."
Baby Moses was brought back to his mother for nursing:
"When thy sister walked along and said, Shall I guide you to one who will take charge of him? So We restored thee to thy mother that her eye might be cooled and she might not grieve............" (ch 20 : v 41)
Mother of Moses was pious woman whom God spoke with AND God filled His love into Moses since beginning:
[20:39] When We revealed to thy mother what was an (important) revelation, (saying),
[20:40] Put him in the ark, and throw it into the river, then the river will cast it on to the bank, (and one who) is an enemy to Me and also an enemy to him will take him up. And I wrapped thee with love from Me; and this I did that thou mightest be reared before My eye."
Thus Prophet Moses (on whom be peace) believed in One God before he was commissioned.
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Prophet Muhammad:
"And He found thee wandering in search (of Him) and guided thee (unto Himself)." (ch 93 : v 8)
The years before he was commissioned:
.......For the purpose of communing with himself and imploring the light and guidance of the Supreme Being concerning the problems that troubled his mind and soul, he formed the habit of retiring, for several days at a time, to a cave on one of the hills a few miles out of Mecca. There he occupied himself in prayer and contemplation. Taking with him a quantity of dates and a little water by way of provisions, he would spend his days and nights in self-examination, in reflecting on the problems that troubled him, and in prayer and supplication to God.......
He himself had never bowed to an idol or indulged in any idolatrous practices. On the physical side, he had preserved complete purity; he had never gambled or taken liquor, and had led an absolutely chaste life. He enjoyed the trust of his fellow townsmen, and was held in respect by them........
Source:
THE EXCELLENT EXEMPLAR - MUHAMMAD
Thus Prophet Muhammad (peace and blessings of Allah be on him) believed and prayed to One God before he was commissioned. He was from the progeny of Prophet Abraham and Ishmael (on whom be peace).
Please also see:
Prophets of God