Today is the first full day of Passover, the week-long holiday (starting last night at Sundown) commemorating the work of the Lord in bringing the people of Israel out of Egypt. The name "Passover" refers to the tenth and final plague, where God sent the angel of death to take every first-born child, but if the Israelites would put the blood of a sacrificed lamb on their doorposts, the angel would "pass over" their house. The key ritual of Passover is the Seder, the family meal celebrated on the first evening of the celebration. All of the parts of the meal are highly symbolic, as shown in LEGO by Joanna, the Bible Belt Balabusta. The four goblets are for the four cups of wine that Jews drink at specific points in the dinner (at the prayer for sanctification, the retelling of the Exodus, the prayer for blessing and the prayer of praise), remembering the four promises of God to bring them out of Egypt. Matzah (the stack of three 2x2 tiles) is the unleavened bread that is eaten to remember the poverty of the enslaved Israelites. Also, God told Moses to have them make bread without leaven, so they would not have to wait for the bread to rise, and therefore would be ready to go at a moment's notice. The maror (the carrot stalk in a cone) is a bitter herb (usually horeradish), eaten to remember the bitterness of slavery. The charoset (the pink flower) is a paste made of fruit and nuts resembling the mortar used by the slaves to build in Egypt. The karpas (flower stem) is a vegetable, often parsely, dipped in salt water to represent the tears of the Israelites (or maybe the dipping of Joseph's coat in blood by his brothers). The zeroah (the bone) is a roasted lamb bone, for the lamb sacrificed on that first Passover, or for the annual sacrifice at the Temple in Jerusalem. The beitzah (the white minifig head) is a roasted egg, commemorating a festival sacrifice, or mourning over the destroyed temple, or spring. The blue tile is a Haggadah, a small book containing the texts read during the seder. The word 'haggadah' means 'telling', since the main purpose of the ritual is telling the story of the Exodus, particularly to the next generation. And therefore using a child's toy to reinforce this lesson for the children is a particularly appropriate use of LEGO here.
BTW, my apologies to my Jewish readers if I got any of the above wrong. That's based on searching around different websites for explanations of the parts of the seder. I'd be happy to be corrected over anything I messed up.