Third:

677. If a person fears that if he uses water, his life will be endangered, or he will suffer from some ailment or physical defect, or the illness from which he is already suffering will be prolonged, or become acute or some complications may arise in its treatment, he should perform Tayammum. However, if he can avoid the harm by using warm water, he should prepare warm water and perform Wudhu, or Ghusl when it is necessary.

Second:

672. If a person is unable to procure water on account of old age, or fear of a thief or a beast, or because he does not possess means to draw water from a well, he should perform Tayammum. The same would apply if acquiring or using water is intolerably difficult.

First:

When it is not possible to procure sufficient water for performing Wudhu or Ghusl.

Tayammum

Tayammum should be performed instead of Wudhu or Ghusl in the following seven circumstances:

Mustahab Ghusls

651. In Islam, several Ghusls are Mustahab. Some of them are listed below:

Exhumation

648. It is Haraam to open the grave of a Muslim even if it belongs to a child or an insane person. However, there is no objection in doing so if the dead body has decayed and turned into dust.

649. Digging up or destroying the graves of the descendants of Imams, the martyrs, the Ulama (scholars) and the pious persons is Haraam, even if they are very old.

650. Digging up the grave is not forbidden in the following nine cases, rather it is obligatory in a few cases:

Namaz – e – Wahshat

(Prayers to be offered for the departed soul on the night of burial)

645. It is Mustahab that on the first night after the burial of a dead person, two Rak’ats of Wahshat prayers be offered for it. The method of offering this prayer is as follows:

Mustahab acts of Burial (Dafn)

Rules about burial of the dead body

620. It is obligatory to bury a dead body in the ground, so deep that its smell does not come out and the beasts of prey do not dig it out, and, if there is a danger of such beasts digging it out, then the grave should be made solid with bricks, etc.

Mustahab acts of Namaz – e – Mayyit

618. The following acts are Mustahab in Namaz – e – Mayyit:

1. A person who offers prayers for the dead body should have had Ghusl or performed Wudhu or Tayammum. And the precaution is that he should perform Tayammum only when it is not possible to perform Ghusl, or Wudhu, or if he fears that if he goes for Ghusl or Wudhu it will not be possible for him to participate in the prayers.