“While he was living there, Reuben had intercourse with Bilhah, his father’s concubine, and Jacob soon heard about it.” (Genesis 35:22 NLT)
Reuben’s sin was costly, although not right away. As the oldest son, he stood to receive a double portion of the family inheritance and a place of leadership among his people. Reuben may have thought he got away with his sin. No more is mentioned of it until Jacob, on his deathbed, assembled his family for the final blessing. Suddenly Jacob took away Reuben’s double portion and gave it to someone else. The reason? “You slept with one of my wives; you dishonored me in my own bed.” (Genesis 49:4)
Sin’s consequences can plague us long after the sin is committed. When we do something wrong, we may think we can escape unnoticed, only to discover later that the sin has been quietly breeding serious consequences.
-- from The Life Application Study Bible