俱舍論記 18.111

18.111

「論曰至施果有殊」者，此即總釋。由所施田總有四種：一趣、二苦、三恩、四德。各有差別，故名田異。由田異故，令彼施體及果有殊。

Regarding "The Śāstra says... the fruits of giving are distinct": this is the general explanation. There are four kinds of fields given to in total: first, destiny (gati); second, suffering (duḥkha); third, gratitude (upakāra); fourth, virtue (guṇa). Each has its distinctions; therefore they are called differences in the field. Because of differences in the field, both the substance of that gift and its results are distinct.