The biblical lead-up is pretty subtle, giving precious little very directly in the way of clues, as befitting hidden treasure. Here's the account of the institution of Chag HaMatzot.
14 ‘Now this day will be a memorial to you, and you shall celebrate it as a feast to the LORD; throughout your generations you are to celebrate it as a permanent ordinance. 15 Seven days you shall eat unleavened bread, but on the first day you shall remove leaven from your houses; for whoever eats anything leavened from the first day until the seventh day, that person shall be cut off from Israel. 16 On the first day you shall have a holy assembly, and another holy assembly on the seventh day; no work at all shall be done on them, except what must be eaten by every person, that alone may be prepared by you. 17 You shall also observe the Feast of Unleavened Bread, for on this very day I brought your hosts out of the land of Egypt; therefore you shall observe this day throughout your generations as a permanent ordinance. 18 In the first month, on the fourteenth day of the month at evening, you shall eat unleavened bread, until the twenty-first day of the month at evening. 19 Seven days there shall be no leaven found in your houses; for whoever eats what is leavened, that person shall be cut off from the congregation of Israel, whether he is an alien or a native of the land. 20 You shall not eat anything leavened; in all your dwellings you shall eat unleavened bread.Exodus 12:14-20
Filling in the blanks is a necessary task, and watching as a student at the Lord's feet is how that is done. In the 12th chapter of another book, another imprint of the 21st day of the first month is presented in a mind boggling dramatic modeling that richly illustrates the appointed fulfillment of the day! This is one of my favorite passages!
Peter had been imprisoned by Herod.
7 And behold, an angel of the Lord suddenly appeared and a light shone in the cell; and he struck Peter’s side and woke him up, saying, “Get up quickly.” And his chains fell off his hands. 8 And the angel said to him, “Gird yourself and put on your sandals.” And he did so. And he *said to him, “Wrap your cloak around you and follow me.” 9 And he went out and continued to follow, and he did not know that what was being done by the angel was real, but thought he was seeing a vision. 10 When they had passed the first and second guard, they came to the iron gate that leads into the city, which opened for them by itself; and they went out and went along one street, and immediately the angel departed from him.Acts 12:7-10
Peter represents the church, and most particularly in this scenario, the Bride. He passes through the iron gate into Jerusalem as out of the flesh realm with its bondage to the law of sin and death. So, when does this occur?
1 Now about that time Herod the king laid hands on some who belonged to the church in order to mistreat them. 2 And he had James the brother of John put to death with a sword. 3 When he saw that it pleased the Jews, he proceeded to arrest Peter also. Now it was during the days of Unleavened Bread. 4 When he had seized him, he put him in prison, delivering him to four squads of soldiers to guard him, intending after the Passover to bring him out before the people. 5 So Peter was kept in the prison, but prayer for him was being made fervently by the church to God. 6 On the very night when Herod was about to bring him forward, Peter was sleeping between two soldiers, bound with two chains, and guards in front of the door were watching over the prison.Acts 12:1-6
This happened on the last day of Chag HaMatzot, on the 21st day of the 1st month. Was this for no reason? Was it for no reason that what's recorded in Acts 2 happened on Shavuot? If you still think Bible events and their dates are random, you really haven't been paying attention to some very important details. These things weren't intended to jump out and slap us to get our attention. They were hidden in plain sight to be revealed in due time for a small number of people on something of a need-to-know basis.
When you grasp the meaning of that prophetic passage in Acts, what happened on the last day of Hag HaMatzot at the time of the Exodus lends the testimony of a confirming witness. I found this page where the events of the day are noted: Chag HaMatzah - scroll down to where it says: "On this 21st Day of Nisan" - where you will discover why many Rabbis pour water on the floor and dance in it to celebrate the last day of the Feast. This is when the people crossed over the sea on dry land in martial array - the very day.
But Moses said to the people, “Do not fear! Stand by and see the salvation of the LORD which He will accomplish for you today; for the Egyptians whom you have seen today, you will never see them again forever.Exodus 14:13
Peter had passed through the iron gate, leaving the bondage of prison many years later but yet on the very anniversary of when the children of Israel had left the land of bondage in similar fashion. Peter had followed the angel, and the gate they came to opened miraculously so they could pass. The Hebrews had followed the angel of God and the sea they came to parted miraculously so they could pass.
19 The angel of God, who had been going before the camp of Israel, moved and went behind them; and the pillar of cloud moved from before them and stood behind them. 20 So it came between the camp of Egypt and the camp of Israel; and there was the cloud along with the darkness, yet it gave light at night. Thus the one did not come near the other all night. 21 Then Moses stretched out his hand over the sea; and the LORD swept the sea back by a strong east wind all night and turned the sea into dry land, so the waters were divided. 22 The sons of Israel went through the midst of the sea on the dry land, and the waters were like a wall to them on their right hand and on their left.Exodus 14:19-22
Coincidence? I'm not buying it.
It must be said that, as the time draws ever nearer for the revealing of the lawless one and Bride Theft following eight days after, the enemy's schemes escalate, working to obscure the paramount truths and to blunt the sharp end of the spear by every means. The counterfeit must become more and more like the genuine. The brighter the flame of the Lord's activity, the brighter the counterfeit in appearance, and the more dense the obscuring smoke blown around it. The Lord's crux moves are of course the most critical, and the Adversary's counter to them must rise to meet them with effective challenges. It only makes sense. It has to be this way.
The Devil is not stupid or feeble. He's been appointed a task by the sovereign God. He leverages a system of nets, in a sense, that will ensnare all but the very elect. Many of his counter-moves will come as preemptive strikes instead of following after as a response, as some might suppose. Satan's game is major league! He knows the entrapment ploys, and has a set-up for everything. To navigate the system you must have a hearing ear and seeing eye, the Lord's provision. No one's going to just get lucky and find their way through the deceitful snares to the narrow gate; the Lord ensures that will not happen.
What I refer to as the Hear-Do cycle is how the eye is trained to see, how the Lord qualifies those who become trustworthy, through obedience. At some point, entrance is given into a level where even the times and seasons become known, in truth. The meaning of events is bound up with the sequence and timing of events. I'm talking about something more than acquiring the ability to parrot a date.
You don't know when something is not going to be unless and until you know when it is going to be.
For those who "get it," I won't need to explain the need to critically observe the differences between those ministering in this late hour. I frequently reference the work of others but I have no loyalties or affiliations, none I'm aware of anyhow. When I direct you to the work of others for a resource, there is plenty I'm grateful for in being able to do it. You have to know that there's no blanket endorsement in that, which is why I often give the figurative caveat about eating the fish and spitting out the bones. You are responsible to test even my words with a critical ear, a discerning ear that hears. There's nothing more valuable because the shepherd's voice is your trustworthy guide.