A goose quill is more dangerous than a lion's claw

Kill not the goose that lays the golden eggs

QUILL, n. An implement of torture yielded by a goose and commonly wielded by an ass. This use of the quill is now obsolete, but its modern equivalent, the steel pen, is wielded by the same everlasting Presence.

Don't kill the goose with the golden egg

Pick the goose as long as it has feathers

What's good for the goose is good for the gander