Chewing up the Meat and Spitting out the Bones- is That Biblical?

In the Discernment department, I hear people frequently say they realize that so and so teaches some things that are bad, but some things they teach are good, so they will just take the good and throw out the bad. They call this method of learning the word of God “Chewing up the meat and spitting out the bones.” But is this how teachers should be followed or how scripture should be learned? No.
In Matthew 7:15 we read,
Beware of false prophets, who come to you in sheep’s clothing but inwardly are ravenous wolves.
It’s a scripture we are familiar with, maybe too overly familiar. Let’s dig down into it again with a fresh eye.
Matthew 7 is the third of three chapters that comprise the Sermon on the Mount, arguably the most important sermon in the entire bible. Jesus is warning, exhorting, and teaching. By Chapter 7, He focuses on judgment/wrath, the broad and narrow road, and judging/discernment. Jesus spends a good deal of time teaching about judging wisely with good discernment. It is here in verse 7 He mentions false prophets.
He opens with the word “Beware.” When a command like this appears, we perk up to an even greater degree than usual. It’s like the word “woe”, indicating the need for special attention to what is being said.
The word “beware” refers to our Lord telling us specifically to be wary of a false prophet. He says they will be numerous and they will be hard to spot. But what is particularly dangerous about false prophets of which we should be aware?

So “Beware” it says – now, that word alone ought to let you know they’re dangerous. “Beware.” Literally, in the Greek it means, hold your mind back from. Don’t ever expose your mind to the influence of a false prophet. Don’t pay attention to, give heed to, follow, notice, devote yourself, don’t even put your mind in his vicinity. They’re dangerous, they pervert the mind, they poison the soul. (source)

People's Temple cult leader Jim Jones

Beware means warning, danger! It tells us that extreme caution is to be employed. The action we
should be taking is not to give any quarter to any part of a false teacher's teachings. To "hold your mind back from" ... that is an interesting phrase. We know the scriptures transform us by the renewing of our mind. The mind is the first battlefield. Not the heart. See the scripture in Romans, it dovetails nicely with Matthew 7:15
Do not be conformed to this world, but be transformed by the renewal of your mind, that by testing you may discern what is the will of God, what is good and acceptable and perfect.
It once again illustrates that there is a severe dichotomy. Either/or. You are either being conformed to the world, OR you are being transformed by the renewal of the mind. There is no chewing meat AND bones and then spitting out bones. Your mind will either be conformed or not. It will be transformed or not. False teaching will poison your mind or not.
And secondly, the verse says we should seek that which is good. We should seek that which is acceptable. We should seek that which is perfect.
The Matthew 7:15 warning and the Romans verse say nothing about ingesting poison just so we can get to some nugget we believe is good. It says nothing about allowing poison into our mind just so we can strain out what we deem as bad. We in our pride think we can chew meat and spit bones even though we are told to seek what is good and acceptable and perfect by the One who is Good and Acceptable and Perfect? We are not to seek what is imperfect and full of bones! We are then choosing not to be careful. This is setting ourselves to be smarter than Jesus! WE are too smart for Jesus? Let it not be so!

You see, we see the results of what they [false teachers] do in 2 Peter 2:2, “Many people follow their pernicious ways.” (source)

Many will follow the false prophets. Do we think we are so strong that we will not be one of the many? Do we think we are so strong that we will be able to ingest poison and spit it out before it affects us?
The subtly of that false prophet can even singe your garment. MacArthur
The second reason, after pride, not to follow false prophets altogether and avoid chewing on meat to spit on bones, is destruction.
Pride goes before destruction, and a haughty spirit before a fall. (Proverbs 16:18)
If we believe we can withstand all the warnings about false prophets, be able to detect to the smallest degree what is good and acceptable and perfect in their teachings, and to in effect be smarter than Jesus and ignore His warnings, then we are proud. And pride sets us up for falling into destruction.
In Maine where I lived for many years, there are sea urchins in the intertidal zone. These marine animals have spikes. If you step on them, they hurt. Some are poisonous. What people say who claim they can "chew the meat" of a false teacher's teachings, and "spit out the bones" is that they have confidence in walking on kelp-covered, slick rocks in bare feet with tide and current pushing them off, and be able to perfectly balance and make progress without slipping and stepping on one of the spines. Or swallowing a bone. Pride. No, eventually they will slip in due time and they will step on a spike and they will be destroyed by the poison the urchin holds for them.
A third and most important consideration is this: if a teacher has shown themselves false by their fruit, and by God-given discernment you've realized this, then nothing they offer will be meat. It may look like meat, just as their garment may look like a sheep's. But that "meat" the prideful ones claim they can chew happily will have worms, e coli, and ground glass in it. For nothing a false teacher has to say is healthy. Nothing. It might sound good...you might think it is helpful, but it is not.
A false prophet has neither a divine commission nor a divine message. He neither speaks for God or from God. He stands in his own authority speaking his own message, and it is utterly false. (source)
Utterly. False.
In the above linked source, the example is given about the horrific and tragic events in 1978 in Jonestown Guyana, where 908 people drank cyanide-laced Kool-Aid and died in the jungle. These people had followed Jim Jones into his cult. Jones, that false teacher, brought them in a long slow descent from Christianity to Jones personally claiming to be Jesus, and when he said so, killed themselves.
There was a man named Tim Stoen. As John MacArthur described,

Here was this fellow attending the First Presbyterian Church of Berkeley and at People’s Temple at the same time. Raised in a G.A.R.B. background – a Fundamentalist, Bible-believing, Christ-honoring people – but exposing his mind to that instead of holding back his mind.  

Jonestown, Guyana, Nov. 1978.
This mass suicide (304 were children) resulted in the greatest single loss of American
civilian life in a deliberate act until the terrorist attacks of September 11, 2001

Tim Stoen was married with a son, and the Stoens followed Jones from California to Guyana to the compound Jones had created. Eventually Grace Stoen left the cult and her husband, she defected. She battled for her son from the States. Tim left the cult year later. They battled for their son, hard, but the suicides occurred before they could get him out of the cult. John's 6-year-old body was discovered in Jones' cabin when the story broke.
Tim Stoen started out well. He had a large ministry in his church, he was regarded as an elder, was seen as mature and solid. However when Jones came to popularity, Stoen divided his mind. He ingested some bones with his meat. The bones will get you every time.
Stoen sadly discovered the hard way what happens when you do not hold your mind back from false teachers. He lost his marriage, his wife, and his son- all destroyed. He lost many years of valuable time he could have been working for the Lord- destroyed. He'd aided and abetted this cult leader in deceiving many- they were destroyed. Aside from the children, when the adults woke up, they were in hell.
False teaching destroys. Do not be so prideful that you think you can detect meat from bones, or even more foolishly believe that any part of a false teacher's food is healthy for the body. It isn't. Beware.