New Defender's Study Bible Notes
13:4 the month Abib. The Israelite religious calendar, as established at this time, is still recognized by modern Jews. It is as follows, in relation to our modern western calendar:
13:5 keep this service. The passover observance was to be kept by the Israelites each year in remembrance and appreciation for what God had done for Israel. As such it became in itself a strong testimony to the Mosaic authorship of the Pentateuch, as well as the deliverance from Egypt. That is, if some group of priests, many centuries later, had invented the whole scenario and then tried to foist it off on the people as having come from Moses, then the fact that no such passover service had been previously practiced by their ancestors, would have immediately revealed the fraud.
13:13 firstling of an ass. As an unclean animal, the ass was not suitable as a sacrifice, but was a valuable animal for service. Since every firstborn animal was henceforth to be sacrificed, the firstborn of an ass must either be slain and discarded, or else redeemed by a sacrificial lamb. The firstborn son of Israelite parents also had to be redeemed by a lamb.
13:16 frontlets. These “frontlets” or “phylacteries” were small pouches containing sections from the laws of Moses, worn on the forehead or the left arm above the elbow. Some orthodox Jews follow this practice even today. The Hebrew word means “prayer case.”
13:18 way of the wilderness. The shortest way to Canaan was by way of the seacoast, where a Philistine colony had been established since even before Abraham’s time. The Egyptians also probably had forces stationed there. More importantly, God had a testing and training program awaiting His people before they would be ready for the conquest of Canaan. There was also an appointment at Mt. Sinai.
13:19 bones of Joseph. Joseph, like his father Jacob, had specifically asked that his remains eventually be buried in the Promised Land, and Moses honored this request. See Genesis 50:25.
13:21 pillar of a cloud. Many naturalistic explanations have been offered to account for this remarkable cloud, but none really fit the description. This glory-cloud called the shekinah was altogether miraculous, giving God’s people constant assurance of His presence with them during their long stay in the wilderness (note also Exodus 40:38; Numbers 9:15-23).