One may tithe from [tevel] of a Jew on behalf of [tevel] of a gentile; from [tevel] of a gentile on behalf of [tevel] of a Jew; from [tevel] of a Jew on behalf of [tevel] of a Cuthean; from [tevel] of a Cuthean on behalf of [tevel] of a Cuthean. R’ Eliezer forbids [tithing] from [tevel] of a Cuthean on behalf of [tevel] of a Cuthean.