[4:29-4:30] O you who believe, consume not your goods between you wrongly, except it be trading through mutual agreement. And kill not yourselves. Surely God is ever Merciful to you. * And whoever does that through aggression and injustice, him We shall certainly expose to a fire; and that for God is an easy matter.
Every thing spent for something other than God is a good spent wrongly. It is said it is being withholding when that is done in an unthinking way and spending when that is not done from a place of witnessing True Reality (ḥaqīqa). All of that is wrong.
And kill not yourselves, meaning by committing sins. It is said its oblique reference is to that which incurs His wrath (s). It is said [it means] by your contemplating [these acts] and considering them.
And whoever does that through aggression and injustice, We will not release him from a fierce punishment. We will entrust [the fire's] inhabitant to it and give it free rein.