barley equal in quantity to the wheat, or pays in advance for silk and accepts horses, cattle, or sheep in its place—this is permissible. A number of scholars of the school, including Ibn Abī Mūsā and al-Sāmirī, the author of al-Mustawʿib, have mentioned this, though only for certain cases. As stated in al-Mustawʿib:

“According to one of the two reported positions, whoever pays in advance for something may not, under any circumstances, accept something of a different kind in its place. According to the other, this is permissible, and he may accept grains inferior to wheat, such as barley and the like, in a volume equal to that of the wheat, but no greater, and not on the basis of its value. Ahmad explicitly stated this.”

In the report transmitted by Abū Tālib, he said:

“If you pay in advance for a kurr of wheat and accept barley instead, there is no harm, since it is less than your entitlement. But do not accept wheat in place of barley.”

Those well acquainted with Ahmad’s explicit statements, however, have reported a broader position: goods owed under a salam contract may be exchanged for anything not sold by volume or weight, without restriction. Abū Hafs al-ʿUkbarī mentioned this in his collection, and Judge Abū Yaʿlā copied it from him in his own handwriting. Thus, if the goods contracted for are sold by volume or weight, he may accept an equal volume of a different variety that is inferior in quality. Likewise, he may accept their value in goods not sold by volume or weight, in whatever form he wishes.

Ibn al-Qāsim related from Ahmad:

“I said to Abū ʿAbd Allāh, ‘If he cannot find the goods for which he paid in advance, but finds something else of the same kind, may he accept it?’

“He said, ‘Yes, if it is inferior to what he is owed.’

“I said, ‘What if he paid in advance for a qafīz of Mosul wheat?’

“He said, ‘Then he may take sult barley in its place, or a qafīz of barley, using the same measure