and the second was that not one of them should ever return to Mecca after leaving it as an emigrant to Allah and His Messenger.

For when you depart from a land in migration to Allah and His Messenger, that land becomes like wealth you have given in charity: just as it is impermissible to reclaim alms once offered, it is impermissible to go back to that land.

The same principle applies to everything a person abandons for Allah’s sake—he must never go back to it.

A present-day example is the decision many people have been blessed to make: removing the television set from their homes in repentance to Allah and in avoidance of the evils it brings. Some then ask, “May we bring it back into the house?”

We answer: No. Once you have removed it for Allah’s sake, do not restore it, for when someone leaves something for Allah, when he forsakes something for Allah, he must not return to it. This is precisely why the Prophet (peace and blessings be upon him) asked his Lord to complete the emigration of his Companions.

His words, “and do not make them turn back on their heels,” mean: do not let them relapse from faith and revert on their heels, because disbelief is regression whereas faith is advancement. This stands in direct opposition to today’s atheists, who brand Islam as “backward” and claim that progress requires a person to shed Islam and embrace secularism—meaning that he draws no line between faith and unbelief, between sin and obedience, Allah forbid. In reality, genuine progress lies in faith.

Those who move forward are the believers; true advancement comes through faith, while apostasy is nothing but a retreat on one’s heels, exactly as the Prophet (peace and blessings be upon him) said here: “and do not make them turn back on their heels.”