What is the ruling on swearing by Allah and not fulfilling the oath, while being unable to offer expiation for the oath due to not possessing its cost and the difficulty of fasting?

If one swears an oath and then breaks it, expiation is required of them: either freeing a slave, or feeding ten needy persons (with a mudd of food for each needy person), or clothing them. If unable to do any of these, then one must fast for three days, and it is recommended that these be consecutive. Scholars have differed on whether the expiation for breaking an oath must be performed immediately or can be delayed. The most accurate view is a detailed one: if the reason for breaking the oath was an act of disobedience, then the expiation is immediately obligatory; otherwise, it is recommended to hasten it without it being obligatory. Expiation becomes binding when one is able to perform it, and if one is unable, nothing is required until they gain the ability.