And the LORD spake unto Moses in the wilderness of Sinai, in the first month of the second year after they were come out of the land of Egypt, saying, Let the children of Israel also keep the passover at his appointed season.–Numbers 9:1-2.
The Lord instructed Moses to teach all Israel to observe the Passover at a definite time, in the proper manner. There were some in the camp who were defiled by a burial detail on the day of Passover and were ceremonially unclean and could not observe the Passover feast. "And there were certain men, who were defiled by the dead body of a man, that they could not keep the passover on that day: and they came before Moses and before Aaron on that day (Num. 9:6). They had a desire to come but the Law prevented them from doing so (Num. 9:7). Moses presented the matter unto the Lord for the answer, "And Moses said unto them, Stand still, and I will hear what the LORD will command concerning you" (Num 9:8). The Lord, in great mercy permitted a second Passover one month later and instructed those that were defiled to keep it in the same manner (Num. 9:10-12).
From this we can learn, whenever the sinner is brought unto the Lord the means do not change. It is always through the sacrifice appointed of the Lord, Christ and Him crucified (ICor.2:2; 1Peter 1:18-20). God has determined to show mercy only in Christ (Rom. 3:19-26). There is just one true gospel that will justify the ungodly (Rom. 5:6-11). Christ is our gospel Passover (1Cor. 5:7; 2Cor. 5:21; 1Peter 3:18).
There were also some in the camp who were clean who refused to observe the Passover, "But the man that is clean, and is not in a journey, and forbeareth to keep the passover, even the same soul shall be cut off from among his people: because he brought not the offering of the LORD in his appointed season, that man shall bear his sin. (Num. 9:13).
From this we can learn, those who think themselves righteous or clean, who refuse to believe the gospel of Christ, shall bear their own sin (Luke 16:15). Because, "He brought not the offering of the LORD, that man shall bear his sin." No greater judgment can be pronounced upon a guilty sinner, "that man shall bear his sin." Our Lord said, "that ye shall die in your sins: for if ye believe not that I am he, ye shall die in your sins. (John 8:24).
Remember this, it is not your unrighteous self (guilt, sin) that will keep you from Christ (Matt. 9:13; 1Tim.1:15). It is your righteous self (goodness, pride) that will keep you from the true Saviour and cause you to find refuge in anything but Christ alone (John 5:39-40; Rom. 10:1-4).
Who then should come, observe and eat the gospel Passover in Christ? Those who are guilty, lost, hungry, and defiled (Isa. 55:1-4:John 6:53-56).