From medieval European and North-African Sephardi responsa we learn that communities lent heqdesh-funds with rabbinic, and even with direct interest to Jews. These practices were not always in congruity with the decisions of the rabbis. I will discuss responsa of Raviah, Meir of Rothenburg, Isaac b. Moses, Avigdor ha-Kohen, Samuel of Bamberg, Jacob Mollin, Israel Isserlein, Moses Mintz, Joseph Colon; Rashba, Rosh, Judah b. Asher, Moses Halavah, Nissim Gerondi, Ribash, Rashbatz, Rashbash and examine in which cases the rabbis prohibited interest between the community and Jewish individuals, as well as why these practices were widespread.
There are two other types of rabbinic interest the allowance or prohibition of which will be dealt with. First, the lending heqdesh money on mortgaged real estate (land, vineyard, house), renting out the estate (/consuming its usufruct), and deducing a stipulated amount from the debt of the debtor, usually yearly, in exchange for the usufruct consumed by the creditor (heqdesh), which amount is however less than the market value of the consumed fruits. This type of security is called “mashkanta be-nakyata” [משכנתא בנכייתא], nakyata meaning deduction [from the verb לנכות]; this deduction makes this interest only rabbinic prohibition. The decisions of Rosh, of Judah b. Asher, and of Alexander Süsslin from Germany will be dealt with.
The second is the lending a certain greater amount of goods like wheat, oil or wine, in order to receive back later the same amount, although the commodity became more expensive or cheaper (se’a be-se’a, סאה בסאה, a measure of grain or liquid, 7.3 l); or paying the money in advance for a foodstuff and receiving it at a later time, although meanwhile its price changed. Sources from Rashba; from the judge R. Joseph bar Asher of Toledo; from R. Moses Halavah and from Ribash will be discussed.