Why Do We Say "Allah ennoble his face" When Sayyiduna Ali is Mentioned?

what is the purpose of saying 'Karram-Allahu wajhahu' after sayyiduna Ali's name? is this permitted and does it have a basis in the deen?

Walaikum assalam,

This became the practice of the early Muslims (salaf) of the Sunni path after extremist groups started cursing the cousin of the Prophet (Allah bless him & give him peace), door of the city of knowledge, and righteous khalifa, the one whose face never bowed to an idol, whom Allah ennobled with blessings unimaginable…

Those god-forsaken people used to say, “May Allah blacken his face,” for unjust criticisms they had against Sayyiduna Ali’s judgments.

In response, the people of the Sunni path made it their habit to say, “Allah ennoble his face,” after mention of Sayyiduna Ali (may Allah be pleased with him and ennoble his face).

It is an inherited practice of the Ummah, passed down with acceptance generation after generation by the scholars, saints, and righteous of the Ummah of the Messenger of Allah (blessings and peace be upon him, his family, and companions). The great Companion, Abdullah ibn Mas`ud (Allah be pleased with him), said, “What the Muslims deem good is good in the sight of Allah.”

This is why the fuqaha tell us the principle that, “Inherited practice cannot be an innovation.” That is, the inherited practice of the Ummah, passed down with acceptance generation after generation, by scholars, saints and righteous without condemnation…

The Prophet (Allah bless him & give him peace) said, “Be with the group, for the group is mercy, and being alone is misery.”

And Allah alone gives success.

Walaikum assalam,
Faraz Rabbani