When those who disbelieve had put in their hearts pride and haughtiness the pride and haughtiness of the time of ignorance, then Allah sent down His Sakinah (calmness and tranquillity) upon His Messenger (SAW) and upon the believers, and made them stick to the word of piety (i.e. none has the right to be worshipped but Allah), and they were well entitled to it and worthy of it. And Allah is the All-Knower of everything.