But the sound view is that, so long as a single name encompasses it, it is one town. Even if this town were to expand so that there were miles or farsakhs between its extremities, it would still be one locality: Friday Prayer would be obligatory upon one living at its farthest eastern end just as it is obligatory upon one living at its farthest western end; and likewise for the north and south, because it is one town.
“There is no more than a farsakh between him and the mosque.” …
His statement, “There is no more than a farsakh between him and the mosque,” is the sixth condition: there must not be more than a farsakh between a person and the mosque. As mentioned previously, a farsakh is three miles, and a mile is twelve thousand cubits. Accordingly, Friday Prayer is not obligatory upon someone who lives more than a farsakh away from the town—if he is outside the town. However, if the town is one unified settlement, then it is obligatory upon him, even if there are several farsakhs between him and the mosque.
Our scholars stated that travelling a farsakh takes an hour and a half when walking or riding camels, not when travelling by car. If there is more than a farsakh between him and the mosque, they said that it becomes obligatory upon him by virtue of others; that is, if Friday Prayer is established while he is in the town, he must attend it; otherwise, he is not required to do so. Thus, there are six conditions for Friday Prayer to be individually obligatory.
[If someone were to ask: What evidence is there for restricting this to a farsakh? The answer is that they say: generally, someone who is more than a farsakh away from the mosque will not hear the call to prayer. Some scholars, however, based the measure on hearing the adhan. Those who set it at a farsakh said that the adhan varies according to the voice of the muezzin, the winds, the elevation of the muezzin, and the quietness of surrounding sounds; therefore, it cannot be precisely determined, whereas a farsakh is a fixed measure. Thus, there is no textual proof for this; rather, it is an underlying rationale. The evidence indicated by the sunnah is hearing the adhan, based on the Prophet’s words, peace and blessings be upon him: “Do you hear the call?” He said, “Yes.” He replied, “Then respond.” (1)]