A good tree is not able to produce bad fruit, nor a bad tree to produce good fruit.

"Either make the tree good and its fruit [is] good, or make the tree bad and its fruit [is] bad, for the tree is known by its fruit.

for each tree is known by its own fruit. For figs are not gathered from thorn plants, nor are grapes harvested from thorn bushes.

But the one who enters through the door is the shepherd of the sheep.

A fig tree is not able, my brothers, to produce olives, or a grapevine figs. Neither can a saltwater spring produce fresh water.