What does Matthew 7:17 mean?
John Gill's Exposition of the Bible
Ver. 17 Even so every good tree bringeth forth good
fruit
As is the tree, so is its fruit; if the tree is good, it will bring
forth good fruit. The tree that brings forth good fruit, is good
antecedent to the fruit it produces; it is first good, and then
puts forth good fruit: it is not the fruit that makes the tree
good, but makes it appear to be so; but it is the goodness of the
tree that makes the fruit good. As a good man does, and will do
good works, but his works do not make him a good man; he is so
before he performs good works, or he would never be able to do
them; these make him appear to be a good man: so a good preacher,
that has an experimental knowledge of the doctrines of the Gospel,
will deliver out sound doctrine, who is first made so by the gifts
and graces of the Spirit of God; and by searching the Scriptures,
and examining his doctrines by them, he will be known and appear to
be a good minister of Jesus Christ, nourished up in the words of
faith and good doctrine; and such a good minister of the Gospel,
out of the good treasure of Gospel truths put into his earthen
vessel, will bring forth, from time to time, good and excellent
truths, to the edification and profit of those that hear: "but a
corrupt tree bringeth forth evil fruit"; if the tree is corrupt,
the fruit will be corrupt; and as is the preacher, so will be his
doctrines: if he is a corrupt preacher, or a man of a corrupt mind,
destitute of the truth, his preaching will be such as will tend to
corrupt both the principles and practices of men; for such evil men
and seducers, out of the evil treasure of false doctrines, which
they have received into their judgments, will bring forth, either
more secretly or openly, evil tenets in their ministry, which prove
of bad consequence to the souls of men.