Al-Nawawī stated that this ḥadīth shows the ruling on congregational prayer is eased when it is raining or when a comparable excuse exists, while it remains emphatically recommended when there is no excuse. It is still legislated for anyone who makes the effort to come and bears the hardship, for in another wording the Prophet said, “Let whoever wishes pray in his dwelling” (1). The report likewise indicates that congregational prayer is prescribed while travelling and that the Friday obligation falls away because of rain or similar circumstances (2).
Ibn Qudāmah said: “As for deep mud, its mere presence is an excuse. Al-Qāḍī related that our scholars hold it to be so, because the hardship that afflicts one’s footwear and clothing is the same as that caused by rain; this is also the position of Mālik …” (3). This opinion is the sounder one, for mud soils clothing and sandals, and a person is liable to slip and injure himself.