The meaning of worshipping Allah as it were upon the edge

Mujahid, Qatadah and others said:

عَلَى حَرْفٍ

Commentary

(And among men there is one who worships Allah (standing) on the verge - 22:11.) Bukhari and Ibn Abi Haim have related from Sayyidna Ibn ` Abbas ؓ that when the Holy Prophet ﷺ migrated to Madinah, people flocked to him and accepted the new religion. But there were some among them whose conversion to Islam was far from being genuine, and whose sole motive for their action was to seek self-advancement, and they lacked conviction. If, after becoming Muslims, favorable circumstances resulted in an increase in their prosperity and their children, they thought Islam was a very good religion, but they were equally ready to condemn it if things went against their personal interests. This verse was revealed to describe such people who were mere opportunists and were easily swayed either way depending on where their selfish interests lay.