In Deuteronomy 15:19-23, Moses is going to bring up the topic of the firstborn again. He first addressed it in chapter 12 and then again in chapter 14. But this time he is going to discuss the sacrifice of the firstborn of the flock and the herd. The doctrine of the firstborn was to have strong significance for the people of Israel, providing a link all the way back to the days before the exodus from Egypt. As a result of God sparing the firstborn son of every Hebrew family, as well as the firstborn of their sheep and bulls, the Israelites were to dedicate these animals as offerings to God. They belonged to Him. And the presence of the Levites among the other tribes was to act as a constant reminder that they stood as substitutes for every firstborn male among the Israelites. The tribe of Levi had been dedicated to God for His service. And the firstborn of the flocks and herds also belonged to God – as tokens of thanks and expressions of worship.