What is meant by guarantee in the case of loss of life, and is it blood money (Diyya)? And what is the difference between digging a well on one's own land and hunting that kills a human, and in both cases is blood money not obligatory because the act was authorized without transgression or negligence?

The term 'guarantee' (ضمان) in the context of damaging a soul refers to either diyya (blood money) or qisas (retaliatory punishment). If the offense against a soul was intentional and the perpetrator is accountable (مكلف), then qisas is obligatory. However, if the perpetrator is not accountable, or if the offense was accidental, then diyya is obligatory.

Digging a well may or may not entail guarantee. If someone digs a well on their own property, they are not liable for anything that falls into it. But if they dig it on property that does not belong to them, then they are liable.

There is a distinction between direct killing, such as shooting at game and hitting a person instead, and killing by causation, such as falling into a well that was permitted to be dug. In the latter case, the digger is not the actual killer; rather, the deceased is the one who caused their own demise. Since the cause was permitted and the digger did not directly cause the killing, there is no guarantee (liability) upon them.