Praise be to Allah, and peace and blessings be upon the Messenger of Allah. To proceed:
Hanifiyyah is the religion of Abraham عليه السلام, based on worshipping Allah alone, affirming His Oneness, and avoiding shirk.
Therefore, whoever lived before the mission of the Prophet Muhammad ﷺ and followed Hanifiyyah, adhering to the religion of Abraham عليه السلام, worshipping Allah alone and associating nothing with Him, was upon Tawhid and the religion of Abraham, and should not be treated like someone who practiced shirk.
Allah says:
“Abraham was neither a Jew nor a Christian, but he was a Hanif, a Muslim, and he was not one of the polytheists.”
[Aal ‘Imran 3:67]
A person who received knowledge of the religion of Abraham عليه السلام and adhered to it is not considered among Ahl al-Fatrah in the intended sense here, because he knew Tawhid and followed what had reached him of the religion of Abraham.
Among the most famous people known for this before Islam was Zayd ibn ‘Amr ibn Nufayl, may Allah have mercy on him. He rejected idol worship, did not adopt Judaism or Christianity, and searched for the true religion until he adhered to the religion of Abraham عليه السلام.
It is authentically reported in Sahih al-Bukhari that when he asked about Hanifiyyah, he was told that it was the religion of Abraham عليه السلام, who was neither a Jew nor a Christian and worshipped none but Allah.
Zayd then declared his adherence to it and said:
“O Allah, I bear witness that I follow the religion of Abraham.”
He used to condemn Quraysh for their idol worship and openly reject the shirk they practiced.
Al-Hafiz Ibn Hajar, may Allah have mercy on him, mentioned that Zayd ibn ‘Amr was among those who sought Tawhid, abandoned idol worship, and avoided shirk, and that he died before the mission of the Prophet ﷺ.
Reports concerning him also state that the Prophet ﷺ prayed for mercy for him and that he died upon the religion of Abraham عليه السلام.
This demonstrates the virtue of those who remained steadfast upon Tawhid and the religion of Abraham before the mission of the Prophet Muhammad ﷺ and did not fall into shirk.
Whoever lived before the mission of the Prophet Muhammad ﷺ and followed true Hanifiyyah, worshipping Allah alone, adhering to the religion of Abraham عليه السلام, and avoiding shirk, was upon Tawhid. Whoever died upon that state is saved, by Allah’s permission.
Such a person is not regarded as someone who turned away from the truth after it had reached him. Rather, he followed what had reached him of the religion of Abraham عليه السلام. One of the best-known examples is Zayd ibn ‘Amr ibn Nufayl, may Allah have mercy on him.
And Allah knows best.