slept through the dawn prayer while travelling with his Companions—as related in the hadith of Abu Qatadah—he instructed Bilal to give the call to prayer. He then prayed the sunnah prayer of dawn, and afterwards prayed the dawn prayer in congregation, as he would normally pray it, reciting aloud (1).
Thus, if some people sleep while travelling and do not wake until after sunrise, we say to them: Do exactly as you normally do: give the call to prayer, say, “Prayer is better than sleep,” pray the sunnah prayer of dawn, then establish the prayer and recite aloud in it.
His statement, “not a condition”: in my copy it appears as “not a condition” in the accusative case. In other copies, it appears in the nominative case. Grammatically, the correct wording is the nominative: “It is not a condition,” with the predicate of an omitted subject understood—that is, “It is not a condition.” As for the accusative wording, it is not correct, because lā cannot contain an implicit pronoun such that we might say its noun is implicit and that “a condition” is its predicate. The meaning is that praying in congregation is not a condition for the validity of the prayer. Therefore, if someone prays alone without an excuse, his prayer is valid, though he is sinful.
NOT A CONDITION ............
Concerning his statement, “not a condition,” someone may ask: Why did he say, “not a condition”?
We say: His statement, “not a condition,” was intended to refute those who hold that it is a condition for the validity of the prayer. Among those who held that it is a condition for the validity of the prayer were Shaykh al-Islam Ibn Taymiyyah, may Allah have mercy on him, and Ibn Aqil. Both were Hanbalis, and this is also one narration from Imam Ahmad. According to this view, if a person prays alone without a legally valid excuse, his prayer is invalid, just as it would be if he abandoned ablution, for example.
This view is weak. What further demonstrates its weakness is that the Prophet, peace and blessings be upon him, said: “The prayer of ...”