One of the signs of the onset of the Hour is that the sun will rise from the west instead of rising from the east. When that happens, it will indicate that the onset of the Hour is very close, and at that time belief will not benefit the disbeliever at all.

The punishment of the grave may be for sins of the heart, the eye, the ear, the mouth, the tongue, the stomach, the private parts, the hand, the foot, and the entire body.

One of the greatest reasons for which Allah has created us – which is one of the greatest tests – is the command to affirm His Oneness (Tawhid) and to worship Him Alone with no partner or associate. For more, see the detailed answer.