Numbers 3:42Meaning & Commentary from the Church Fathers

We want to emphasize that we are not referring to all the firstborn of Israel, which would include approximately 150,000 among a population of around two million, based on about 600,000 adult males. Instead, we are considering only the newborn firstborns from the time of the Exodus to the census. Our understanding is grounded in the fact that the command regarding firstborns is introduced for the first time in Exodus (Exodus 13:2, 12). Given that the Jewish people have consistently been a vigorous and prolific community, we maintain that the annual number of male newborn firstborns—accounting for one for every 27 adult husbands—remains relatively modest.