2, 12 Every firstborn man or beast must be consecrated to me. It is mine.
13 Every firstborn donkey must be redeemed with a lamb. If you don't redeem it, you must break its neck. And you must redeem all your male firstborn children.
14 When your son asks you why you're doing this, say to him, Because when God brought us out of Egypt, he killed all of their firstborn sons and animals. So I sacrifice to God all of my firstborn animals, and I redeem all my firstborn children.
9, 16 It will be a sign on your hand and a memorial between your eyes, so God's law will be in your mouth.
Through the wilderness of the Red Sea
17 God led the people through "the wilderness of the Red Sea" to avoid crossing the land of the Philistines.
21 He went before the Israelites in a pillar of cloud by day and a pillar of fire by night.
The Red Sea crossing
145-6 When the Pharaoh heard that the Israelites left, he got his chariot ready to follow them. 7 He took 600 chariots and chased after them. 21 When the Israelites arrived at the Red Sea, Moses parted the sea and the Israelites walked across on dry land.
24-25 God saw the Egyptians pursue them, so he removed their chariot wheels.
6 Your right hand, O Lord, has dashed the enemy in pieces.
8 You make great floods with a blast from your nostrils.
10 You drown people by blowing with your wind, etc.
The waters of Marah
22 The Israelites resumed their journey but had no water to drink. 23 After three days without water, they came to Marah, where there was water. But it was too bitter to drink.
24 So they murmured against Moses, saying, "What shall we drink?" 25 Moses cried to God, and God showed him how to throw a tree into the water to make it taste sweet.
A few more words about this episode
You must redeem all your male firstborn children. (13:13)
This verse says you must redeem your firstborn sons, but it doesn't say how they are to be redeemed. By sacrificing a lamb or goat - like you do for firstborn donkeys? And if you don't redeem them, must you break their necks? The Bible doesn't say.
But the rabbis have filled in what the Bible left out. You must redeem your sons with five silver coins to a kohen (a descendant of Aaron).
God avoids leading the Israelites through "the land of the Philistines" hundreds of years before the Philistines were established in Canaan.
The way through the "land of the Philistines" was the well-established trade route between Egypt and Canaan that Abraham, Isaac, Jacob, and Jacobs sons made frequently, and apparently with little difficulty. It was a few hundred kilometers and would have taken a couple of weeks - rather than the 40 years that the Israelites supposedly spent following God around the Sinai peninsula during the Exodus.
A sign on your hand and a memorial between your eyes (13:9,16)
These verses are interpreted by the rabbis to mean, "Wear the commandments on your hand and head (between the eyes)." See also Dt 6:8
They are called phylacteries - leather boxes worn on the forehead and wrist containing a few words that are meant to represent the entire Torah.