Bechorot 5 - Were Firstborn Sanctified in the Desert?

Rabbi Yochanan said that the firstborn were sanctified in the desert, since the Merciful One said " Sanctify for Me every firstborn ," but Resh Lakish said that they were not, as in the phrase " When God brings you to the land of Canaanites... you will set apart every firstborn to God "  - then, but not prior to that.

Rabbi Yochanan, "But the firstborn brought sacrifices in the desert, before the Tabernacle was built!?" Resh Lakish: "These were firstborn born in Egypt, but not born in the desert. In fact, I have a question against you from your proof: the Tabernacle was built one year after the Exodus, so how could one-year-old firstborn bring sacrifices?" Now, that is so obvious, how could Rabbi Yochanan ask such a question? He answers, "If there was no firstborn sanctification in the desert, the previous one also ceased."

Kuntrukos the Roman minister asked Rabban Yochanan ben Zakkai, "There were two hundred talents of silver collected, but only one hundred was used. Moses your teacher must have been a thief, a kidnapper who hid half the people, or he just could not count." Rabban Yochanan replied, "Moses our teacher was a trustworthy treasurer and a skilled accountant. However, the talent of the Temple was twice the size of the common unit, thus, the 200 talents collected were only 100 in terms of the Temple units." How does he know that? From Ezekiel's phrase, "Sixty shekels will be a talent for you," whereas a regular talent was only thirty shekels.

Art: George Cruikshank I - The thief  - Jonathan Wild Thief Turned Thief Taker Throwing Richard Trenchard Down The Well