Seven times, God says to eat unleavened bread for seven days. He is very clear.
It is commonly held that Unleavened Bread is about putting sin out of our lives. And while that is an aspect, if we were to go through all of God's instructions for Unleavened Bread, we would see that His reason and emphasis are different. What God overwhelmingly emphasizes is His deliverance, not our work of avoiding leavening and thus sin (Exodus 12:17; Exodus 13:3, 8-9; 23:15; 34:18; Deuteronomy 16:3).
The overarching reason for that feast, and the reason we eat unleavened bread for seven days, is to remember God's deliverance. When we get to the New Testament, Jesus identifies Himself as the bread of God - the bread of life. He was entirely unleavened.
Further, Paul tells us in I Corinthians 5:8, Therefore let us keep the feast, not with old leaven, nor with the leaven of malice and wickedness, but with the unleavened bread of sincerity and truth. Christ is the embodiment of sincerity and truth. He is the One who delivered us from this present, evil age, from spiritual bondage, from the power of darkness. And it is through the strength that He supplies that we have the means to overcome sin. And that strength comes from ingesting His word and beseeching Him to live His life in us every day.
The unleavened bread that God says we must eat for seven days represents Christ Himself. To miss eating the unleavened bread of sincerity and truth is to miss out on the divine connection with our Savior. Our minds should rebel at the thought of skipping that.
It is similar with Passover. The bread and wine are the symbols of Passover. It wouldn't be Passover without them. These things may just be symbols, but these symbols signal to God our intent and our desire to fulfill all righteousness, even in the symbols.
In the same way, we keep the Feast of Unleavened Bread for seven days by eating unleavened bread each day and not merely avoiding leavening. Consider what neglecting to eat the unleavened bread of life every day would signal to God. The symbols matter.
Faithful and righteous Daniel chose to spend the night in a cave of lions rather than give up his bread of life for a single day. That's how important his connection with God, and being strengthened by God, was to Daniel. It is those who know their God who will be strong and carry out great exploits, but that strength and knowledge of God come from continually partaking of what, or of Whom the unleavened bread represents.
Maybe you have never caught this, but the instructions here are not just about our food for the week, but God includes multiple mentions of our dwellings - our houses, our quarters, or those areas that are under our authority. Again, that is not by chance. Every word matters. By the First Day of Unleavened Bread, all the leavening must be removed from our houses, and then we must be vigilant about not letting anything leavened into our houses. In all our dwellings, we eat unleavened bread.
Houses are dwellings that are made to last. They have foundations. They represent being settled and having a more-or-less permanent place of one's own. Of course, nothing physical is truly permanent, but there is greater and longer-term stability in houses compared to booths. Houses give a measure of certainty. They become a base from which we operate and return to. Under normal circumstances, we aren't concerned that they will be blown or washed away. They have foundations, and they become foundational to us.
We can apply that to the lessons of Unleavened Bread. God says repeatedly that the reason we keep that feast and eat unleavened bread is because of what He did. He delivered Israel from Egypt and the power of the Pharaoh. Likewise, He delivered us from this present evil age and its adversarial ruler. He delivered us from spiritual Egypt and has given us a new home.
The Israelites only had physical houses, but we have a spiritual house that can give us far greater … . . .