For a narrative explanation of this source sheet, see There's More to Eating Matzah Than Remembering We Were Slaves by Ayalon Eliach in Ha'aretz, April 21, 2016, available at: http://www.haaretz.com/jewish/the-jewish-thinker/.premium-1.715607
(3) You shall not eat anything leavened with it; for seven days thereafter you shall eat unleavened bread, poor bread —for you departed from the land of Egypt hurriedly—so that you may remember the day of your departure from the land of Egypt as long as you live.
These two passages offer the generally cited explanation for eating matzah and refraining from eating chametz on Passover: It commemorates the hasty exodus from Egypt because the ancient Israelites did not have time for their bread to rise as they were fleeing. There are, however, a few textual difficulties with this being the only, or even the primary, explanation for these eating practices.
(א) וַיֹּ֤אמֶר יְהוָה֙ אֶל־מֹשֶׁ֣ה וְאֶֽל־אַהֲרֹ֔ן בְּאֶ֥רֶץ מִצְרַ֖יִם לֵאמֹֽר׃ (ב) הַחֹ֧דֶשׁ הַזֶּ֛ה לָכֶ֖ם רֹ֣אשׁ חֳדָשִׁ֑ים רִאשׁ֥וֹן הוּא֙ לָכֶ֔ם לְחָדְשֵׁ֖י הַשָּׁנָֽה׃ (ג) דַּבְּר֗וּ אֶֽל־כָּל־עֲדַ֤ת יִשְׂרָאֵל֙ לֵאמֹ֔ר בֶּעָשֹׂ֖ר לַחֹ֣דֶשׁ הַזֶּ֑ה וְיִקְח֣וּ לָהֶ֗ם אִ֛ישׁ שֶׂ֥ה לְבֵית־אָבֹ֖ת שֶׂ֥ה לַבָּֽיִת׃ (ד) וְאִם־יִמְעַ֣ט הַבַּיִת֮ מִהְיֹ֣ת מִשֶּׂה֒ וְלָקַ֣ח ה֗וּא וּשְׁכֵנ֛וֹ הַקָּרֹ֥ב אֶל־בֵּית֖וֹ בְּמִכְסַ֣ת נְפָשֹׁ֑ת אִ֚ישׁ לְפִ֣י אָכְל֔וֹ תָּכֹ֖סּוּ עַל־הַשֶּֽׂה׃ (ה) שֶׂ֥ה תָמִ֛ים זָכָ֥ר בֶּן־שָׁנָ֖ה יִהְיֶ֣ה לָכֶ֑ם מִן־הַכְּבָשִׂ֥ים וּמִן־הָעִזִּ֖ים תִּקָּֽחוּ׃ (ו) וְהָיָ֤ה לָכֶם֙ לְמִשְׁמֶ֔רֶת עַ֣ד אַרְבָּעָ֥ה עָשָׂ֛ר י֖וֹם לַחֹ֣דֶשׁ הַזֶּ֑ה וְשָׁחֲט֣וּ אֹת֗וֹ כֹּ֛ל קְהַ֥ל עֲדַֽת־יִשְׂרָאֵ֖ל בֵּ֥ין הָעַרְבָּֽיִם׃ (ז) וְלָֽקְחוּ֙ מִן־הַדָּ֔ם וְנָֽתְנ֛וּ עַל־שְׁתֵּ֥י הַמְּזוּזֹ֖ת וְעַל־הַמַּשְׁק֑וֹף עַ֚ל הַבָּ֣תִּ֔ים אֲשֶׁר־יֹאכְל֥וּ אֹת֖וֹ בָּהֶֽם׃ (ח) וְאָכְל֥וּ אֶת־הַבָּשָׂ֖ר בַּלַּ֣יְלָה הַזֶּ֑ה צְלִי־אֵ֣שׁ וּמַצּ֔וֹת עַל־מְרֹרִ֖ים יֹאכְלֻֽהוּ׃
(1) The LORD said to Moses and Aaron in the land of Egypt: (2) This month shall mark for you the beginning of the months; it shall be the first of the months of the year for you. (3) Speak to the whole community of Israel and say that on the tenth of this month each of them shall take a lamb to a family, a lamb to a household. (4) But if the household is too small for a lamb, let him share one with a neighbor who dwells nearby, in proportion to the number of persons: you shall contribute for the lamb according to what each household will eat. (5) Your lamb shall be without blemish, a yearling male; you may take it from the sheep or from the goats. (6) You shall keep watch over it until the fourteenth day of this month; and all the assembled congregation of the Israelites shall slaughter it at twilight. (7) They shall take some of the blood and put it on the two doorposts and the lintel of the houses in which they are to eat it. (8) They shall eat the flesh that same night; they shall eat it roasted over the fire, with unleavened bread and with bitter herbs.
God commands the Israelites to eat the Paschal lamb with matzah while they are still in Egypt, before the exodus. They had more than a week after this instruction to prepare and bake regular bread. This instruction, therefore, can't be about commemorating a rush out of Egypt, because nobody had rushed anywhere yet.
This instruction about avoiding chametz and eating matzah on all future Passovers was given while the Israelites were still in Egypt, before the exodus had even occurred. It could not, therefore, have been about commemorating hastily baked bread that had not even been baked yet.
Additionally, Passover is not the only time chametz is replaced with matzah. This happened all year in the Tabernacle/Mishkan:
What do Passover and the Tabernacle/Mishkan have in common?
(7) It is not because you are the most numerous of peoples that the LORD set His heart on you and chose you—indeed, you are the smallest of peoples; (8) but it was because the LORD loved you and kept the oath He made to your fathers that the LORD freed you with a mighty hand and rescued you from the house of bondage, from the power of Pharaoh king of Egypt.
The Israelites are told that God redeemed them purely out of love, not because they did anything to deserve it. Passover celebrates this redemption and, hence, this unconditional love. God's presence among the Israelites in the Tabernacle/Mishkan is the ultimate goal of this act of divine love:
(מד) וְקִדַּשְׁתִּ֛י אֶת־אֹ֥הֶל מוֹעֵ֖ד וְאֶת־הַמִּזְבֵּ֑חַ וְאֶת־אַהֲרֹ֧ן וְאֶת־בָּנָ֛יו אֲקַדֵּ֖שׁ לְכַהֵ֥ן לִֽי׃ (מה) וְשָׁ֣כַנְתִּ֔י בְּת֖וֹךְ בְּנֵ֣י יִשְׂרָאֵ֑ל וְהָיִ֥יתִי לָהֶ֖ם לֵאלֹהִֽים׃ (מו) וְיָדְע֗וּ כִּ֣י אֲנִ֤י יְהוָה֙ אֱלֹ֣הֵיהֶ֔ם אֲשֶׁ֨ר הוֹצֵ֧אתִי אֹתָ֛ם מֵאֶ֥רֶץ מִצְרַ֖יִם לְשָׁכְנִ֣י בְתוֹכָ֑ם אֲנִ֖י יְהוָ֥ה אֱלֹהֵיהֶֽם׃ (פ)
(44) I will sanctify the Tent of Meeting and the altar, and I will consecrate Aaron and his sons to serve Me as priests. (45) I will abide among the Israelites, and I will be their God. (46) And they shall know that I the LORD am their God, who brought them out from the land of Egypt so that I might dwell among them, I the LORD their God.
But what does God's unconditional love have to do with chametz and matzah?
Encyclopedia Britannica
Bread... The first bread was made in Neolithic times, nearly 12,000 years ago, probably of coarsely crushed grain mixed with water, with the resulting dough probably laid on heated stones and baked by covering with hot ashes. The Egyptians apparently discovered that allowing wheat doughs to ferment, thus forming gases, produced a light, expanded loaf, and they also developed baking ovens... Although raised bread originally relied upon spontaneous fermentation, bakers learned to produce fermentation with yeast....
Bread is arguably the most basic food that humans eat. The difference between matzah and chametz is that matzah is flour and water mixed together and cooked immediately; whereas chametz is flour mixed with water that ferments and expands. Matzah is this basic food in its unleavened, unchanged state; whereas chametz is the same food once it has begun to go through a process of change.
Food is the most prominent thing that we intake completely into our bodies. It thus represents full acceptance. Refraining from chametz reminds us that full acceptance is not conditioned on being transformed, on being "leavened" into better people. Rather, matzah -- especially during Passover and in the Tabernacle/Mishkan -- serves as a physical reminder that we are worthy of full acceptance and love even in our "unleavened" state.