Sh'mot 13:1-2 Then the L-RD spoke to Moshe, saying, "Sanctify to Me every first-born, the first offspring of every womb among the sons of Israel, both of man and beast; it belongs to Me."
First Born - in Hebrew the word is Bekor. The word Bekor is masculine. So this refers to the firstborn males.
The first-born was considered special. This is done for a special reason. Surely you know. It points us to His firstborn (begotten) son Yeshua HaMashiach.
The corresponding letter to this chapter is Mem- revelation; revealed and concealed.
The first born male being set apart is revealed to us.
Sh'mot 13:3-10 And Moshe said to the people, "Remember this day in which you went out from Egypt, from the house of slavery; for by a powerful hand the L-RD brought you out from this place. And nothing leavened shall be eaten. On this day in the month of Aviv, you are about to go forth. And it shall be when the L-RD brings you to the land of the Kena'ani (Canaanite), the Hitti (Hittite), the Emori (Amorite), the Hivi (Hivite) and the Y'vusi (Jebusite), which He swore to your fathers to give you, a land flowing with milk and honey, that you shall observe this rite in this month. For seven days you shall eat Matzah (unleavened bread), and on the seventh day there shall be a feast to the L-RD. Matzah (Unleavened bread) shall be eaten throughout the seven days; and nothing leavened shall be seen among you, nor shall any leaven be seen among you in all your borders. And you shall tell your son on that day, saying, 'It is because of what the L-RD did for me when I came out of Egypt.' "And it shall serve as a sign to you on your hand, and as a reminder on your forehead, that the law of the L-RD may be in your mouth; for with a powerful hand the L-RD brought you out of Egypt. Therefore, you shall keep this ordinance at its appointed time from year to year.
Leavened - Hametz
The month of Abib - It later became the month of Nisan.
And it shall serve as a sign to you on your hand, and as a reminder on your forehead - Some believe that HaShem was speaking in a figurative sense here and meant that they were to be able to recall what G-d' law demanded of them. Others take this literally and strap on their left arm and their foreheads leather prayer boxes that contains parchment of scriptures containing the verses from Sh'mot (Exodus) 13:1-16; D'varim (Deuteronomy) 6:4-9; and D'varim (Deuteronomy) 11:13-21.
Here the L-rd commands that Pesach is observed from year to year. We listen to HaShem because we want to please Him.
Sh'mot 13:11-16 "Now it shall come about when the L-RD brings you to the land of the Kena'ani (Canaanite), as He swore to you and to your fathers, and gives it to you, that you shall devote to the L-RD the first offspring of every womb, and the first offspring of every beast that you own; the males belong to the L-RD. But every first offspring of a donkey you shall redeem with a lamb, but if you do not redeem it, then you shall break its neck; and every first-born of man among your sons you shall redeem. And it shall be when your son asks you in time to come, saying, 'What is this?' then you shall say to him, 'With a powerful hand the L-RD brought us out of Egypt, from the house of slavery. 'And it came about, when Pharaoh was stubborn about letting us go, that the L-RD killed every first-born in the land of Egypt, both the first-born of man and the first-born of beast. Therefore, I sacrifice to the L-RD the males, the first offspring of every womb, but every first-born of my sons I redeem.' "So it shall serve as a sign on your hand, and as phylacteries on your forehead, for with a powerful hand the L-RD brought us out of Egypt."
Every first offspring of a donkey you shall redeem with a lamb - Since donkeys were not sacrificial animals, a lamb was substituted for it. Donkeys are considered unclean animals and not fit for sacrifice. (See Numbers 18:15)
The First born is dedicated to the L-rd. With a powerful hand the L-rd brought us out of Egypt by using Moshe. Egypt was a type of sin. On a higher level, it points to the L-rd who also brought us mercy and brought us out of sin by using Yeshua. We, His children, are redeemed through His firstborn son or the Lamb of G-d - Yeshua.
Tehillim (Psalms) 80:15-19 Even the shoot which Your right hand has planted, And on the son whom You have strengthened for Yourself. It is burned with fire, it is cut down; they perish at the rebuke of Your countenance. Let Your hand be upon the man of Your right hand, Upon the son of man whom You made strong for Yourself. Then we shall not turn back from You; Revive us, and we will call upon Your name. O L-RD G-d of hosts, restore us; Cause Your face to shine upon us, and we will be saved. NASU
Hebrews 1:1-14 G-d, after He spoke long ago to the fathers in the prophets in many portions and in many ways, in these last days has spoken to us in His Son, whom He appointed heir of all things, through whom also He made the world. And He is the radiance of His glory and the exact representation of His nature, and upholds all things by the word of His power. When He had made purification of sins, He sat down at the right hand of the Majesty on high, having become as much better than the angels, as He has inherited a more excellent name than they. For to which of the angels did He ever say, "YOU ARE MY SON, TODAY I HAVE BEGOTTEN YOU"? And again, "I WILL BE A FATHER TO HIM, AND HE SHALL BE A SON TO ME"? And when He again brings the firstborn into the world, He says, "AND LET ALL THE ANGELS OF G-D WORSHIP HIM." And of the angels He says, "WHO MAKES HIS ANGELS WINDS, AND HIS MINISTERS A FLAME OF FIRE." But of the Son He says, "YOUR THRONE, O G-D, IS FOREVER AND EVER, AND THE RIGHTEOUS SCEPTER IS THE SCEPTER OF HIS KINGDOM. "YOU HAVE LOVED RIGHTEOUSNESS AND HATED LAWLESSNESS; THEREFORE G-D, YOUR G-D, HAS ANOINTED YOU WITH THE OIL OF GLADNESS ABOVE YOUR COMPANIONS." And, "YOU, L-RD, IN THE BEGINNING LAID THE FOUNDATION OF THE EARTH, AND THE HEAVENS ARE THE WORKS OF YOUR HANDS; THEY WILL PERISH, BUT YOU REMAIN; AND THEY ALL WILL BECOME OLD LIKE A GARMENT, AND LIKE A MANTLE YOU WILL ROLL THEM UP; LIKE A GARMENT THEY WILL ALSO BE CHANGED. BUT YOU ARE THE SAME, AND YOUR YEARS WILL NOT COME TO AN END." But to which of the angels has He ever said, "SIT AT MY RIGHT HAND, UNTIL I MAKE YOUR ENEMIES A FOOTSTOOL FOR YOUR FEET"? Are they not all ministering spirits, sent out to render service for the sake of those who will inherit salvation?
Sh'mot 13:17-18 Now it came about when Pharaoh had let the people go, that G-d did not lead them by the way of the land of the P'lishtim (Philistines), even though it was near; for G-d said, "Lest the people change their minds when they see war, and they return to Egypt." Hence G-d led the people around by the way of the wilderness to the Red Sea; and the sons of Israel went up in martial array from the land of Egypt.
G-d did not lead them by the way of the land of the P'lishtim (Philistines) - This would have been along the shore of the Mediterranean Sea and the shortest, route.
Martial array - Just like an army, the Israelites marched in orderly ranks. In B'MidBar (Numbers) 10:11-33 there is a detailed description of the order of the tribes as they marched through the wilderness.