The sounder view is that the agent is not believed against the principal without supporting evidence, nor is the guardian of an orphan believed without proof. Thus, if the guardian asserts that he handed the orphan’s property over to him after the latter came of age, he must establish that claim with evidence, according to the correct opinion.

According to the sound position, neither an agent nor a depositary may, once the owner has demanded his property, insist: “I will not return it unless there are witnesses present.” A usurper, however, and anyone whose word regarding restitution is not otherwise accepted, may require that condition.

If someone says, “The rightful claimant has appointed me as his agent to receive from you what you hold of his—whether a debt or a specific item,” and the debtor believes him, it is permissible to hand the property over to him; yet the authoritative view is that the debtor is not obliged to do so unless the claimant produces evidence of his agency.

If, on the other hand, the man says, “He has transferred the debt to me (hawala) and instructed me to collect it from you,” and the debtor accepts his statement, payment becomes obligatory according to the sounder view.

I add: If he says, “I am his heir,” and the debtor believes him, then, according to the school, delivery is likewise obligatory. Allah knows best.