Tunic refers to an outer garment, a cloak of sorts. This garment was very valuable at the time. Many peasants had only one outer cloak and would pursue whatever means necessary to get it back it if were seized. 1 It was used for bedding by the poor, and it was legally protected under old covenant law (Exodus 22:25–26; Deuteronomy 24:12–13). To relinquish a tunic would be to relinquish a very necessary and prized possession. A possession that someone else does not (ordinarily) have a right to have. 2
40 And if anyone would sue you and take your tunic,let him have your cloak as well.