Why did God give Alexander, Hymenaeus, Jannes, Jambres, and Philetus over to a reprobate mind?

First of all, let me just clarify the content of your question. The scripture doesn't actually say that God gave Alexander, Hymenaeus, Jannes, Jambres and Philetus over to a reprobate mind. What it does say is that Alexander and Hymenaeus were delivered by Paul unto Satan. Of Jannes, Jambres and Philetus it says they erred/resisted the truth. I don't wish to split hairs but it does help when studying the Bible to see exactly what it does say.

Now, to look at exactly what God did with these individuals, we need to look at the passages concerning them and see the individual circumstances.

If we look at Jannes and Jambres we see that they are not mentioned by name until well into the New Testament, although their works are mentioned near to the start of the Bible in the book of Exodus.

In 2 Timothy 3 we read of what I believe to be the corrupt church. Notice, the passage refers to the last days and talks of those "Having a form of godliness, but denying the power thereof: from such turn away." Of these we go on to read, "Ever learning, and never able to come to the knowledge of the truth." It is in this context that Paul, writing under the inspiration of the Holy Spirit, refers to the works of Jannes and Jambres. Some things to notice here about Jannes and Jambres, together with those like them:

1. They resist the truth.
2. They are of corrupt minds.
3. They are reprobate concerning the faith.
4. They will not continue any further.
5. Their folly will be manifest to all.

If we turn to Exodus 7, we see what the apostle was referring to, although Jannes and Jambres are unnamed here (as always, the best commentary on the Bible is the Bible itself).

Exodus 7:10-13 [10] And Moses and Aaron went in unto Pharaoh, and they did so as the LORD had commanded: and Aaron cast down his rod before Pharaoh, and before his servants, and it became a serpent. [11] Then Pharaoh also called the wise men and the sorcerers: now the magicians of Egypt, they also did in like manner with their enchantments. [12] For they cast down every man his rod, and they became serpents: but Aaron's rod swallowed up their rods. [13] And he hardened Pharaoh's heart, that he hearkened not unto them; as the LORD had said.
See All... And Moses and Aaron went in unto Pharaoh, and they did so as the LORD had commanded: and Aaron cast down his rod before Pharaoh, and before his servants, and it became a serpent. Then Pharaoh also called the wise men and the sorcerers: now the magicians of Egypt, they also did in like manner with their enchantments. For they cast down every man his rod, and they became serpents: but Aaron's rod swallowed up their rods. And he hardened Pharaoh's heart, that he hearkened not unto them; as the LORD had said.

1. They resist the truth - they withstood Moses who was doing as the Lord commanded.
2. They were of corrupt minds - they were sorcerers and enchanters.
3. They were reprobate concerning faith - they stood in Pharaoh's court against the people of God.
4. They could not continue any further - Aaron's rod totally defeated them.
5. Their folly was manifest to all - their "defeat" occurred in the presence of Pharaoh, his servants and the wise sorcerers.

It seems to me that Jannes and Jambres are examples of those "reprobate concerning the faith" because they have a form of godliness yet deny the power thereof. They refuse to believe the truth, although they have been faced with it, and God allows them to continue in their own "religious ways" until that day when "their folly shall be manifest".

With regard to Philetus, we only read of him once in the Bible, and that is in the same passage as Hymenaeus so we can see how the Lord dealt with them together.

The Lord's dealings with Alexander and Hymenaeus are interesting. The key passage it seems to me is when they are both mentioned together in 1 Timothy 1:18-20 [18] This charge I commit unto thee, son Timothy, according to the prophecies which went before on thee, that thou by them mightest war a good warfare; [19] Holding faith, and a good conscience; which some having put away concerning faith have made shipwreck: [20] Of whom is Hymenaeus and Alexander; whom I have delivered unto Satan, that they may learn not to blaspheme.
See All....

1 Timothy 1:18-20 [18] This charge I commit unto thee, son Timothy, according to the prophecies which went before on thee, that thou by them mightest war a good warfare; [19] Holding faith, and a good conscience; which some having put away concerning faith have made shipwreck: [20] Of whom is Hymenaeus and Alexander; whom I have delivered unto Satan, that they may learn not to blaspheme.
See All... This charge I commit unto thee, son Timothy, according to the prophecies which went before on thee, that thou by them mightest war a good warfare; Holding faith, and a good conscience; which some having put away concerning faith have made shipwreck: Of whom is Hymenaeus and Alexander; whom I have delivered unto Satan, that they may learn not to blaspheme.

It seems to me that further insight into the "blasphemes" committed by these two men (certainly Hymenaeus but also Philetus) are recorded in 2 Timothy 2:16-18 [16] But shun profane and vain babblings: for they will increase unto more ungodliness. [17] And their word will eat as doth a canker: of whom is Hymenaeus and Philetus; [18] Who concerning the truth have erred, saying that the resurrection is past already; and overthrow the faith of some.
See All....

2 Timothy 2:16-18 [16] But shun profane and vain babblings: for they will increase unto more ungodliness. [17] And their word will eat as doth a canker: of whom is Hymenaeus and Philetus; [18] Who concerning the truth have erred, saying that the resurrection is past already; and overthrow the faith of some.
See All... But shun profane and vain babblings: for they will increase unto more ungodliness. And their word will eat as doth a canker: of whom is Hymenaeus and Philetus; Who concerning the truth have erred, saying that the resurrection is past already; and overthrow the faith of some.

If we look at these two passages we see some interesting things. I'm going to stick my neck on the line and say that I believe they were Believers, and the Lord is dealing with them as such.

1. Timothy is charged to hold faith and a good conscience - Hymenaeus and Alexander had but put it away.
2. They were delivered unto Satan to learn not to blaspheme, NOT to a loss of salvation.
3. Hymenaeus and Philetus were linked to profane and vain babblings, increasing to more ungodliness.
4. Their word is destructive. Canker is a disease which slowly eats away at its host.
5. They have erred in the truth.
6. They have overthrown the faith of some.

These are serious errors found in the lives of these men. They needed to learn the error of their ways, and if they wouldn't heed the words of the apostle, then perhaps the only option left was to deliver them unto Satan for a time to serve this purpose. There is another example of this in scripture which perhaps endorses this view.

In 1 Corinthians 5 we read of a brother who was involved in fornication with his father's wife. Again, this is serious error and the brethren there are told to "deliver such an one unto Satan for the destruction of the flesh, that the spirit may be saved in the day of the Lord Jesus."

It seems to me that the delivering unto Satan of this brother was in a sense an act of judgment/punishment for his sin. However, it was only for a time and did NOT involve a loss of salvation. In fact, we see the outcome of this "deliverance" in 2 Corinthians 2:6-9 [6] Sufficient to such a man is this punishment, which was inflicted of many. [7] So that contrariwise ye ought rather to forgive him, and comfort him, lest perhaps such a one should be swallowed up with overmuch sorrow. [8] Wherefore I beseech you that ye would confirm your love toward him. [9] For to this end also did I write, that I might know the proof of you, whether ye be obedient in all things.
See All....

2 Corinthians 2:6-9 [6] Sufficient to such a man is this punishment, which was inflicted of many. [7] So that contrariwise ye ought rather to forgive him, and comfort him, lest perhaps such a one should be swallowed up with overmuch sorrow. [8] Wherefore I beseech you that ye would confirm your love toward him. [9] For to this end also did I write, that I might know the proof of you, whether ye be obedient in all things.
See All... Sufficient to such a man is this punishment, which was inflicted of many. So that contrariwise ye ought rather to forgive him, and comfort him, lest perhaps such a one should be swallowed up with overmuch sorrow. Wherefore I beseech you that ye would confirm your love toward him. For to this end also did I write, that I might know the proof of you, whether ye be obedient in all things.

I think the apostle is saying here, concerning this same brother who was delivered unto Satan:

1. He's suffered enough.
2. He should be forgiven.
3. He should be comforted.
4. He should be upheld so that he's not broken beyond repair.
5. He should be welcomed back into the fold.

This I believe is the purpose of delivering a man unto Satan.

In closing, I'd just like to look briefly at your thought of God giving people over to a reprobate mind. I'd not looked at this before but have noticed some interesting points whilst studying your question.

In Romans 1:28And even as they did not like to retain God in their knowledge, God gave them over to a reprobate mind, to do those things which are not convenient;
See All... we read of God giving some over to a reprobate mind. The interesting thing about these people is that they indulged themselves in all things unclean and abhorrent to God, yet they knew Him initially.

Romans 1:21Because that, when they knew God, they glorified him not as God, neither were thankful; but became vain in their imaginations, and their foolish heart was darkened.
See All... Because that, when they knew God, they glorified him not as God, neither were thankful; but became vain in their imaginations, and their foolish heart was darkened.

Romans 1:28And even as they did not like to retain God in their knowledge, God gave them over to a reprobate mind, to do those things which are not convenient;
See All... And even as they did not like to retain God in their knowledge, God gave them over to a reprobate mind, to do those things which are not convenient;

Romans 1:32Who knowing the judgment of God, that they which commit such things are worthy of death, not only do the same, but have pleasure in them that do them.
See All... Who knowing the judgment of God, that they which commit such things are worthy of death, not only do the same, but have pleasure in them that do them.

It seems to me here that God is giving these people over to a reprobate mind, to do these things, because in denying Him, these are the things they choose to do themselves.

Looking further at the thought of reprobate, in Jeremiah 6:30Reprobate silver shall men call them, because the LORD hath rejected them.
See All... we read, "Reprobate silver shall men call them, because the LORD hath rejected them."

The question is, what did they do that the Lord should reject them and cause them to be called reprobate? The answer is found in the earlier part of the chapter.

• verse 7 - God's grief over Israel
• verse 10 - The rejection of the word of the Lord
• verse 11 - The fury of the Lord
• verse 13 - The false prophet/priest
• verse 14 - The false message of peace
• verse 16 - The remedy
• verse 19 - The wrath of God because of the rejection of Him
• verse 30 - The people are called reprobate

Again here we see a people who have a knowledge of God yet through rejecting Him and His word they are called reprobate.

As we have already seen, of Jannes and Jambres the scripture says, "reprobate concerning the faith". Their problem? "Having a form of godliness, but denying the power thereof:"

In Titus 1:16They profess that they know God; but in works they deny him, being abominable, and disobedient, and unto every good work reprobate.
See All..., talking of those who are defiled and unbelieving we read, "They profess that they know God; but in works they deny him, being abominable, and disobedient, and unto every good work reprobate."

Here, I think, is the scriptural meaning of reprobate. It is professing to know God, but in works denying Him. This is the point Paul is making in 2 Corinthians 13:5-6 [5] Examine yourselves, whether ye be in the faith; prove your own selves. Know ye not your own selves, how that Jesus Christ is in you, except ye be reprobates? [6] But I trust that ye shall know that we are not reprobates.
See All..., "Examine yourselves, whether ye be in the faith; prove your own selves. Know ye not your own selves, how that Jesus Christ is in you, except ye be reprobates? But I trust that ye shall know that we are not reprobates."

In conclusion, it seems to me that if I have understood the scriptures correctly, it is Believers who are delivered unto Satan for a specific purpose as a result of specific deeds. This deliverance is NOT a loss of salvation, it has an end in view. On the other hand, it also seems apparent that it is unbelievers who are given over to a reprobate mind, those who profess to know God but deny Him in their works. Reprobate, as I see it, has the thought of rejection by God of those who ought to know better.