V.2 What the Israelites were about to be told was to be the beginning of a whole new way of life for them.
V.3-5 “A lamb ... the lamb ... your lamb”; that brings it personally to each Israelite (See 1 Pet. 1:18-20).
V.6 They had to be sure the lamb was perfect.
V.7 They had to “take of the blood” of the killed lamb and put it where God told them.
V.8 Notice the word “roast.” The lamb was never to be roasted ever after, in the keeping of the Passover. It was to be boiled (seethed) in water as 16:23. Roasting exposed the lamb directly to the fire. The Lord Jesus was exposed to the fire of God’s judgment on the cross, once. When we remember the Lord Jesus by taking the bread and the wine it is a remembrance of what He did once.
V.8-11 All were to eat the rest of the lamb, as people all ready to leave Egypt. Like a believer starting out in his new life.
V.12-13 The tenth and final judgment, by which the Lord did what He had promised.
V.14 This special memorial feast was for the Israelites, as the Lord’s Supper (1 Cor. 11:23-26) is now for us Christians.
V.15-20 “Seven days” is a “complete” period, starting immediately after the feast of verse 14! 1 Corinthians 5:6-8 gives the meaning of this seven-day feast for Christians. All our Christian life, right from the moment we were saved we are to act sincerely (honestly, uprightly) and according to the truth of God’s Word. The leaven (a picture of evil) was to be cleared out of their houses — evil is to be put out of our life.