For a good tree brings not forth corrupt fruit; neither does a corrupt tree bring forth good fruit.
All Commentaries on Luke 6:43 Go To Luke 6
Tertullian of Carthage
AD 220
In order that they may be able to establish and settle their threefold theory, or "trinity "in all its characteristics as to the several natures, because "a good tree cannot produce evil fruit, nor a corrupt tree good fruit; and nobody gathers figs of thorns, nor grapes of brambles.".
Of his conceit from the simple passage of our Lord's saying, which has reference to human beings and not divine ones, wherein He disposes of those examples of a good tree and a corrupt one;