Translation:

5. Said (the father): "My (dear) little son! relate not thy vision to thy brothers lest they concoct a plot against thee: for Satan is to man an avowed enemy!

Notes (Tafseer)

1634. The young lad Yusuf was innocent and did not even know of his brothers' guile and hatred, but the father knew and warned him.

1635. The story is brought up at once to its spiritual bearing. These wicked brothers were puppets in the hands of Evil. They allowed their manhood to be subjugated by Evil, not remembering that Evil was the declared opposite or enemy of the true nature and instincts of manhood.