Indebtedness in Islam is not just about monetary or any other material loan. It can also be spiritual, or moral. Each of these is considered a problem for which Islam proffers a solution.
In the spiritual realm, a Muslim may become a debtor when he skips certain daily prayers (Salat). And, until he observes such prayers, no matter how late, he remains a spiritual debtor. He may also become a debtor when he misses some days of fasting in Ramadan for whatever reason or when he fails to pay Zakah at the appropriate time.
Also, his refusal to perform Hajj when he is capable of doing so may amount to indebtedness. In each of these cases, the only rectification which amounts to payment of debt is to atone for the omission. Such rectification can be made by the debtor himself or by someone else (in the case of Zakah and hajj).
As for Salat the rule is different. No other person can help to pay any debt incurred by you. The payment must be done by the very person who incurred the debt. It must be remembered that there is no excuse for missing Salat.
In the case of fasting, there is a temporary indebtedness and there is a permanent one. An example of a temporary indebtedness is that of a menstruating woman or a wayfarer or a sick person. Each of them is to rectify the omission by himself/herself when Ramadan is over.
But a person who is unable to fast due to old age or permanent ailment is not expected to fast after Ramadan. What he has to do is feeding one indigent person each day of Ramadan. That is permanent indebtedness.
Other areas of indebtedness in Islam include Zakah and Hajj. Zakah can be paid on behalf of the estate owner either by his offspring or the beneficiaries of his legacy. This often happens posthumously or if the principal turns infamy.
Hajj, on the other hand, can only be performed by proxy if disability prevents the person concerned from going through its rigour or he is unable to perform that function till his death. Any good Muslim from among his children, relatives or friends can do it on his behalf.
The intention of rectifying material indebtedness by proxy must be in the name of the debtor and the source of funding must be pure. As for moral indebtedness, it may come in form of promise or reciprocation of good deed.
In Islam, promise, especially a voluntary one is a debt, which must be paid. For instance, a deferred dowry in marriage is a debt that must be paid no matter how long it takes. Ditto the case of an orphan’s property under one’s custody which is promised to be returned. Both must be paid as at when due based on fear of Allah. There are many other forms of promises.
All these types of debts are between man and Allah. They need no witnesses except where evidence is required. The one which requires witnesses is contained in chapter 2:282 of the Qur’an. It is about money and other material matters. This verse (the longest in the Qur’an) deals extensively with the issue of indebtedness and emphasizes the documentation of such a debt between the creditor and the debtor in the presence of witnesses who must append their signature to the document.
It does not matter whether the debt in question is between a husband and his wife or between a mother and her daughter. The intention is to create a peaceful co-existence, within the Muslim community, which no debt should interrupt. It is better not to make promise than to change one’s mind after making a promise without informing the person to whom promise is made.
Another form of debt is the boycott of sexual intercourse either by the husband or wife for an untenable reason. From the day a marriage is consummated a knot of legitimate sexual indebtedness has been tied. And except for a very cogent reason which must be understandable to both parties, no one of them should boycott intercourse deliberately.
Ramadan fasting, therefore, or any religious activities in the sacred month should not be used as an excuse for refraining from intercourse without getting the consent of the other party. Whoever does that has deviated from the fulfilment of a major promise. And that in itself is a debt which must be paid.