Bayhaqi 15702 — "Let a man of wealth spend according to his wealth"

Imam al-Shafi'i (may Allah be pleased with him) said regarding the maintenance owed by a (husband) of limited means: "It is one mudd per day, by the mudd of the Prophet (peace and blessings be upon him), from the (common) food of the town."
He said: "I set this obligatory amount at one mudd on the basis of the evidence from the Messenger of Allah (peace and blessings be upon him) regarding the man who had intercourse with his wife during the month of Ramadan: he (peace and blessings be upon him) gave him a basket containing fifteen sa' for (feeding) sixty poor people, which comes to one mudd for each poor person. The basket was of fifteen sa'; it used to be made to that measure so that four baskets would make one wasq. However, the one who narrated the hadith to them introduced a doubt into it: whether it was fifteen sa' or twenty sa'."

It is reported from Sa'id bin al-Musayyib (may Allah have mercy on him), concerning the story of the Bedouin who had intercourse with his wife in Ramadan, that he said: A basket of dates was brought to the Messenger of Allah (peace and blessings be upon him), and he (peace and blessings be upon him) said: "Take this and give it in charity." And he mentioned it (i.e. the long hadith). Ata' (may Allah have mercy on him) said: I asked Sa'id (may Allah have mercy on him) how many dates were in that basket. He said: Between fifteen and twenty sa'.