Says R’ Shimon: What is [the difference] between half shekels and a sin-offering? Half shekels have a set limit, whereas a sin-offering does not have a set limit. R’ Yehudah says: Even half shekels have no set limit, for when Israel returned from the [Babylonian] exile darkons were their shekels; later selaim were their shekels; [still] later teva’in were their shekels and they wished to contribute dinars [as their half shekels]. Said R’ Shimon [to R’ Yehudah]: Nevertheless, they all gave a like amount; whereas [in the case of] a sin-offering, this [person] brings one worth a sela, another brings one worth two [selaim], and yet another brings one worth three [selaim].