His statement, “not because of illness,” means that it is not valid to perform an obligatory prayer on one’s mount merely due to illness, because a sick person can make the mount kneel, dismount to the ground, and pray. However, if we know that, were this sick person to dismount, he would be unable to mount again because he has no one to help him mount, then—which may indeed occur—he may pray on the mount, because this is a greater and more serious hardship than being inconvenienced by rain.
Thus, the author’s statement, “not because of illness,” is not unrestricted. Rather, we say: not because of illness when he is able to dismount and then remount. But if he is unable to do so, then he may pray on the mount due to illness, because that is more severe than mud and the like.
Section
Whoever undertakes a permissible journey …
His statement, “Section”: the author, may Allah have mercy on him, mentioned that there are three excuses by which the manner of prayer changes:
- Travel.
- Illness.
- Fear.
After mentioning illness as an excuse, the author followed it by mentioning travel as an excuse, saying, “Whoever undertakes a permissible journey.” “Whoever” is a conditional noun, and conditional nouns are generally understood to convey universality. It therefore includes every traveller: male or female, free person or slave, young or old.
His statement, “a permissible journey”: linguistically, travel is leaving one’s place of residence.