Q1: Is it permissible that the mahr agreed upon in a temporary marriage be
reciting some Qur’anic verses and giving the reward to the wife as a gift? Or it
should be a material and tangible thing.
Q2: If not, then in case that a girl had conducted temporary marriage several
times and in every time her mahr was just reciting certain chapter of the Qur’an
and giving its reward to her as a gift, is her previous marriage contract ruled
null?
And is the sexual intercourse they did considered as fornication?
A1: Mahr of a temporary marriage should either be money/property or something of
monetary value like teaching [her] a craft or how to read or the like and just
giving her the reward of reading Qur’an cannot replace that.
A2: All the previously settled contracts, mentioned in the question, are void.
The subsequently happened sexual relationships — if the two partners were
ignorant of contract/s nullity — were not ruled as harām, rather they were ruled
as mistakenly done coitus. If sexual intercourse and penetration have taken
place after those void contracts while the wife was not aware of their nullity,
she has the right to claim (mahr al-mithl) — mahr of women with the same station
— from the husband.