The LORD spoke to Moses and Aaron in Egypt.
References for Exodus 12:1
He said, "From now on, this month will be your first month. Each of your years will begin with it.
"Speak to the whole community of Israel. Tell them that on the tenth day of this month each man must get a lamb from his flock. A lamb should be chosen for each family and home.
"Suppose there are not enough people in your family to eat a whole lamb. Then you must share some of it with your nearest neighbor. You must add up the total number of people there are. You must decide how much lamb is needed for each person.
"The animals you choose must be males that are a year old. They must not have any flaws. You may choose either sheep or goats.
Take care of them until the 14th day of the month. Then the whole community of Israel must kill them when the sun goes down.