Ata (may Allah have mercy on him) said: When a man has intercourse with his wife during her menstruation, he should give half a dinar in charity. One of those present said: Hasan (al-Basri, may Allah have mercy on him) says to free a slave? He replied: I do not prevent you from that; seek nearness to Allah as much as you can. That is, along with repentance and seeking forgiveness, the more charity you give, the better.
Hadith Referenceسنن دارمي / من كتاب الطهارة / 1153