A Serpent brought the gift of a rose to Jupiter who refused the gift as accepting it would put him in debt to a Serpent. Not a good thing.
If you receive a gift you must befriend the giver.
L’Estrange version
Jupiter had presents made him upon his wedding-day, greater, or less, from all living creatures. A serpent brought him a rose in his mouth for an offering. The thing was acceptable enough, but not the presenter; for (says Jupiter) though gifts are wellcome to me, of themselves, I must not yet receive any from a serpent.
Moral
He that receives a present, contracts an obligation; which a body would be asham’d of in the case of an ill man; for it looks toward making a friendship with him.