“The believer is like a bee, feeds upon the goodness, relieves a burden of goodness (honey), lands upon a branch softly so as not to break it and when falling into the water does not pollute it.” ~ Saying by Mohammed (as)
"The Messenger of Allah said: “By the One in whose hand is the soul of Muhammad, the believer is like a bee which eats that which is pure and wholesome and lays that which is pure and wholesome. When it lands on something it does not break or ruin it.”
The bee only eats from flowers which are tayyib (pure and wholesome). It is not attracted to repulsive things, unlike other insects. Likewise the believer only eats that which is pure and wholesome.