A few major sins regarding which severe warnings have been mentioned
To ascribe partners to Allah. To shed the blood of someone unjustly.
To practise witchcraft and charms by childless women during the confinement of another woman so that the child of that woman may die and she may have a child. This also amounts to murder.
To taunt or torment one’s parents.
To commit adultery.
To devour the wealth of orphans, e.g. many women usurp the wealth and belongings of the deceased husband and deprive the children of their share. To deprive the daughters of their share in the inheritance. To accuse a woman of adultery even on the slightest doubt.