Today’s Scripture reading is Exodus 12:12-13.
Verse 13, "When I see the blood, I will pass over you and the plague shall not be upon you to destroy you."
You probably started humming the song from the church hymnbook.  "When I see the blood, when I see the blood, when I see the blood, I will pass, I will pass over you."  This hymn most assuredly came from Exodus 12:13.  The last stanza says, "O great compassion! O boundless love! O loving-kindness, faithful and true! Find peace and shelter under the blood, And I will pass, will pass over you."  The blood of Jesus Christ has the power to save every sin-sick soul that turns to Him for salvation.  He is the Lamb of God "slain from the foundation of the world".  His sacrifice has freed us from the penalty of sin, the power of sin, and one day from the very presence of sin!
Rejoice!