and so too do those who remain behind solely because a valid excuse holds them back.

Another example is the report established in the two Sahīhs from Abū Mūsā, who narrated that the Prophet (may Allah bless him and grant him peace) said:

“When a servant falls ill or travels, he is credited with the deeds he used to perform when healthy and at home.”

If someone regularly performed a deed when healthy and at home, then ceased doing it only because of illness or travel, this establishes that he stopped because of inability and hardship, not because his intention had weakened or faltered. He therefore possesses the same firm resolve as the person who performs the deed; only diminished ability prevents him from acting. Although a traveller may be able to perform the deed with hardship—as is also the case with certain illnesses—the ability recognized by Islamic law is that which allows the deed to be performed without harm outweighing its benefit. Thus Allah Most High says:

“Pilgrimage to the House is a duty owed to Allah by those who are able to make their way there.”

And He says:

“Whoever cannot do so must feed sixty needy people.”

The same applies to similar passages. What Islamic law takes into account is not merely the ability to perform an act by whatever means possible. Rather, that ability must involve no harm outweighing its benefit, or even equalling it.

Another example is the established saying of the Prophet (may Allah bless him and grant him peace):

“Whoever equips a fighter has himself fought, and whoever takes good care of his family in his absence has himself fought.”

And his saying:

“Whoever provides a fasting person with food to break his fast will have a reward equal to his, without diminishing the fasting person’s reward in the least.”

For a military campaign requires striving both in person and with wealth. When one commits his person and another his wealth, and both possess firm resolve, each is a fighter