In nature you will never see or find a plant that can change its fundemental nature - impossible. You will never find figs (good works) growing on a thistle bush (evil nature). You will never find grapes (good works) growing on a thorn bush (evil nature) - Mt. 7:16-18. If you can demonstrate different we are all awaiting your evidence? If you cannot, then Jesus is denying the very thing you claim is true that something can change its own nature and produce good (Mt. 12:33).
Your interpretation makes Christ look foolish to his audiance as his audiance (unlike you) are fully aware that such is an absolute impossibility while you are making Christ demand it is possible. You believe something "clean" can come out of something "unclean" when God's word says "not one." You believe that persons described by Christ as "being evil" can "DO" good (when the text says no such thing but uses "good" as an adjective to describe "things" not the person giving those things).
So is there an honest bone in your body? We wait for evidence from nature to support your interpretation that figs can come from thistles and grapes can come from thorn bushes OR that thorn bushes can "make" themselves fig producing bushes and thistles can "make" themselves grape producing bushes as this is what is required to prove your intepretations to be correct! We wait for the evidence that such can be found in the daily life of the audiance he spoke or even today???? Is there an honest bone in your body?
16 Ye shall know them by their fruits. Do men gather grapes of thorns, or figs of thistles?
17 Even so every good tree bringeth forth good fruit; but a corrupt tree bringeth forth evil fruit.
18 A good tree cannot bring forth evil fruit, neither can a corrupt tree bring forth good fruit.
Notice that the "figs" and "grapes" are defined in verses 17-18 as "good fruit" and "thistles" and "thorns" defned as "corrupt...evil tree".
Mt 12:34
O generation of vipers, how can ye, being evil, speak good things? for out of the abundance of the heart the mouth speaketh.
Here is a parallel text with the one that Winman has been repeating over and over again trying to prove that those "being evil" are capable of doing "good."
The rhetorical question by Christ implies they cannot speak "good" things but only have that appearance in the sight of men but as we shall see the nature of the heart dictates the nature of what is expressed in words and actions.
Notice, that Christ defines their nature as "vipers....being evil." The very same description "being evil" found in Winman's proof text. Here this refers to the condition of the heart as verses 34-35 proves this and "things" in verse 35 refer to external manifestations of the heart (words, deeds).
Second, that this description of their nature is in the form of a question "HOW can ye....being evil SPEAK GOOD THINGS"?
Third, notice his explanatory assertion that the source of speaking is from the heart - "for out of the abundance of the heart the mouth speaketh." In other words, "vipers, how can ye being evil" in regard to YOUR HEART speak "good" things as it is the nature of the heart that determines the moral value of what comes out of the mouth. Then he says,
35 A good man out of the good treasure of the heart bringeth forth good things: and an evil man out of the evil treasure bringeth forth evil things.
In other words, the nature of the words must be judged by the nature of the heart. In other words, what appears only to be "good" things coming from the mouth to men is not "good" in God's sight as God judges the moral value of the words by the heart not by the nature of the content of the words. God looks on the heart and in God's sight nothing good can come forth from an evil heart as an "evil man out of the EVIL treasure bringeth forth evil things."
Notice that these two verses are the conclusion of the following Matthew 12:33:
33 Either make the tree good, and his fruit good; or else make the tree corrupt, and his fruit corrupt: for the tree is known by his fruit.
34 O generation of vipers, how can ye, being evil, speak good things? for out of the abundance of the heart the mouth speaketh.
35 A good man out of the good treasure of the heart bringeth forth good things: and an evil man out of the evil treasure bringeth forth evil things
Notice that "things" in this passage refers to EXTERNAL manifestations of the heart (words, actions). So also, in this passage "the tree" and the "heart" are one and the same. The words "being evil" refers to the condition of their heart which can only bring forth "evil" and cannot bring forth good because it requires a "good man" with a "good heart" to bring forth "good" things.
The phrase "make the tree" in this passage does not refer to changing the nature of the tree as no tree can do that. Jesus is rebuking their hypocrisy. Be one thing or the other, but don’t pretend to goodness!" Their evil hearts were being concealed by words with "good" content because their works did not match their words. Stop being hypocrits by your "good" mouth when your heart is evil by the inconsistency between your words and works. Be consistent with your heart and stop speaking hypocritical words that imply to men that that you are "good" instead of "being evil" in heart. In regard to Christ, "make the tree" means be consistent with what you say about Christ. How can you claim Christ is empowered by the Devil when his words and works are in keeping with God's Word, so be consistent with yourselves and with Christ as you speak one thing and do another whereas Christ's word's match his works.