When      a wife lets her husband off paying the Mahr
Question

                There was a sistuation where a father asked for his daughter as Mahr, a Quran straight away and to follow $20,000 later, The brother is unable to pay this amount and the wife would like to pardon him, of this amount, is it permissable?
Also what if the wife didnt pardon this amount and they divorced soon after would he still have to pay the amount to her after the divorce?
Is it permissable for a brother to say that he would pay in Mahr somthing which is not in his means?
Praise be to Allah.There is nothing wrong with a wife letting her husband off paying the Mahr, because Allaah says (interpretation of the meaning):
“but if they, of their own good pleasure, remit any part of it to you, take it, and enjoy it without fear of any harm (as Allâh has made it lawful)” [al-Nisaa’ 4:4]
 This deferred payment becomes due in the case of divorce after the consummation of the marriage, even if the time-period involved is short – unless the woman demands khul’ [a kind of divorce instigated by the wife] and gives up her right to the money, as a compensation to the husband for leaving him. This is OK is the khul’ is done for a legitimate reason and not just for the sake of getting the money. Allaah says (interpretation of the meaning):
“… and you should not treat them with harshness, that you may take away part of the Mahr you have given them, unless they commit open illegal sexual intercourse…” [al-Nisaa’ 4:19]
It is permissible for the husband to say “I will give you such and such as a Mahr”, even if he does not own it; he should explain to them that this is to be paid later rather than sooner, and it will be a debt that he owes. And Allaah knows best.