If a man awakens in a state of ritual impurity (junub) at the time of the Fajr prayer call (iqamah), and he chooses to perform ghusl, will he miss the congregational prayer? Or can he perform ablution (wudu') and pray in congregation at the mosque, then perform ghusl and pray the two rak'ahs of Fajr? Or is it obligatory for him to perform ghusl even if he misses the congregational prayer?

A person in a state of major ritual impurity (junub) must perform a full ritual bath (ghusl) for prayer. Their prayer is not valid with only ablution (wudu'). They must perform ghusl even if it means missing congregational prayer. If they wake up late and fear that the prayer time will expire if they perform ghusl, the majority of scholars hold that they are still obliged to perform ghusl, because the time for them begins when they wake up, based on the Prophet Muhammad's (peace be upon him) saying: "Indeed, there is no negligence in sleep. Negligence is only in wakefulness. So, if one of you forgets a prayer or sleeps through it, let him pray it when he remembers it." Therefore, if water is available, and they fear that the prayer time will expire if they busy themselves with obtaining and using it, they are not permitted to perform tayammum (dry ablution). Rather, ghusl is obligatory for them, even if the time expires.