Exodus 12:25 in the King James Version
And it shall come to pass, when ye be come to the land which the LORD will give you, according as he hath promised, that ye shall keep this service.
Context
24 You shall observe this thing for an ordinance to you and to your sons forever.
25 It shall happen when you have come to the land which the LORD will give you, as he has promised, that you shall keep this service.
26 It will happen, when your children ask you, ‘What do you mean by this service?’