The Passover

Numbers 9:1-14
Celebrate it at the appointed time, at twilight on the fourteenth day of first month, in accordance with all its rules and regulations.
Tell the Israelites: ‘When any of you or your descendants are unclean because of a dead body or are away on a journey, they are still to celebrate the Lord’s Passover, 11 but they are to do it on the fourteenth day of the second month at twilight. 
But if anyone who is ceremonially clean and not on a journey fails to celebrate the Passover, they must be cut off from their people for not presenting the Lord’s offering at the appointed time. They will bear the consequences of their sin.
A foreigner residing among you is also to celebrate the Lord’s Passover in accordance with its rules and regulations. You must have the same regulations for both the foreigner and the native-born.
No one may opt out of celebrating the Passover. But the absentee and anyone ritually unclean at the time may observe the feast one month later.
Why?
Because Passover is salvation of the Lord to all Israelite so they have to remember this day in every generation.
Even foreigner residing among them have to observe this regulation, for God looks men is equal in Israelite.
At twilight on the 14 day of first month, is the time when God asked Israelite when they were slaved in Egypt.
How?
Remember the salvation of the Lord in my life. Do not forget the grace and mercy of the Lord!