After saying that “the whole congregation of the assembly of Israel must slaughter ” the lamb, Moses specified when on Nisan 14 they were to do so. ​ — Read Exodus 12: 5, 6.
يَكْمُنُ ٱلْجَوَابُ جُزْئِيًّا فِي وَصِيَّةِ ٱللهِ إِلَى ٱلْإِسْرَائِيلِيِّينَ .‏