Genesis 29:26 KJV
And Laban said, It must not be so done in our country, to give the younger before the firstborn.
Genesis 29:26, King James Version
In context
25 And it came to pass, that in the morning, behold, it was Leah: and he said to Laban, What is this thou hast done unto me? did not I serve with thee for Rachel? wherefore then hast thou beguiled me?
26 And Laban said, It must not be so done in our country, to give the younger before the firstborn.
27 Fulfil her week, and we will give thee this also for the service which thou shalt serve with me yet seven other years.