Reading 1 - Exo 12:13
"The blood will be a sign for you on the houses where you are; and when I see the blood, I will pass over you. No destructive plague will touch you when I strike Egypt" (Exo 12:13).
As to the word for "passover", compare the "remission"/passing over of sins: Rom 3:25. Literally, the Hebrew "pesach" means to "hover over", to protect: the same word occurs in Isa 31:5; and the general idea comes in Psa 34:7; Heb 1:14.
"The term 'pesach' denotes the Passover offering and more generally the feast centering on that sacrifice, which was eaten at night... The word has been connected with a Hebrew verb meaning 'protect' (Isa 31:5) or 'limp' or 'skip' (2Sa 4:4; 1Ki 18:21,26)" (Anchor Bible Dictionary).
The Hebrew verb is a rare and tricky word, and "authorities" come up with several different possibilities... but the idea of "hovering over, or protecting" is supported by Isa 31:5, where the same verb occurs, and where the context explains its meaning: "As birds flying, so will the LORD of hosts defend Jerusalem; defending also he will deliver it; and passing over (same verb!) he will preserve it." (This is Jerusalem being defended from Sennacherib's army.)
The "birds flying" connects with the Passover angel (or angels)... but the LORD is not "passing by" Jerusalem -- He is "defending" and "delivering" and "preserving" it. It may be, in fact, that there were two very different "Angels of the LORD" at work on Passover night in Egypt -- or better yet, two "legions" of Angels! One Angel (and his "merry band"!) was the "Destroying Angel". The other Angel (and his company) was the "Passover or Hovering-Over Angel", if you will. While Angel No. 1's company went about killing all the firstborn, Angel No. 2's company stood guard at the homes sprinkled with the blood of the Passover lambs, and said, "No, not here! we don't want your business. Keep on going!"
It's a little like the Persian laws in Esther: that is, the first law decrees death for all Jews, which cannot be undone... but the second decree gives them a way out! Here, in Exodus, the decree is: "Kill the firstborn... everywhere"... but God's second law gives the way out: "... except those who are sprinkled with the blood".
In the broader sense, this is really what mortality is all about:
"Death passes upon all men",
BUT "... those who trust in the blood of Christ are delivered from the otherwise-universal death!" The Passover picture suggests the cherubim wings of God, as the One (through His angels?) who hovers over His children... like a mother bird flutters over and protects and nurtures her young.
The Psalms have some great passages along these lines: "under the shadow of God's wings" -- a half dozen or so -- all employing the same figure of speech (Psa 17:8; 36:7; 57:1; 61:4; 63:7; 91:1). And Jesus employs the same figure of speech also when he says to Jerusalem: "O Jerusalem, Jerusalem, thou that killest the prophets, and stonest them which are sent unto thee, how often would I have gathered thy children together, even as a hen gathereth her chickens under her wings, and ye would not!" (Mat 23:37). Words spoken by our Savior on the very eve of Passover, and in the shadow of the cross!
Reading 2 - Psa 66:12
"We went through fire and water, but you brought us to a place of abundance" (Psa 66:12).
"Fire" is the pillar of fire in the wilderness, or the "burning bush" (Exo 3:2) -- typifying Israel's experience of trials. "Water" is the Red Sea and the Jordan River (v 6), the national "baptism" to which Israel was submitted (1Co 10:1,2). Through these testings and trials, God brings His people out of bondage and into a place of "abundance", or possibly "freedom." This pictures the release of the Jews from bondage from Egypt. The KJV translates "a wealthy place" -- perhaps with reference to the plunder of Egypt, received as gifts by the Israelites, and the richness of the Land of Canaan -- which God had prepared for them.
Reading 3 - Mark 1:1
"The Gospel of Mark opens with the words:
'The beginning of the gospel about Jesus Christ, the Son of God.'
We do not notice the concentrated wonder of the last three words, for we have heard them too often. Why does it not strike us as astounding that God should have a Son? It did those who first heard it. For the disciples of Jesus, it was the supreme confession of faith --
'Thou art the Son of God, Thou are the King of Israel',
as another Gospel records from an early disciple; for His enemies, it was the culminating blasphemy, 'and they all condemned him to be worthy of death.'
"The whole Book vibrates with high excitement, supreme hope, crashing despair, and sudden restoration. There is deep-rooted loyalty, black treachery, stirring devotion, and revolting murder. We must recapture the ability to respond to these movements if we would read the Bible as it is. We cannot close our hearts. We must try to live in the events through which we move" (Alfred Norris, "On Reading the Bible" 21,22).