Is Penal Substitution Biblical?

The other thread, "Is Penal Substitution immoral?" spawned a different question in the discussion - is penal substitution Biblical? I've moved it up here to give it more visibility as it's another vital question to discuss.

My discussion partner identifies himself by nothing more than Nick. Let's hear him...

Let me highlight some specific points then, and I will be arguing along the lines of Scripture and leave the philosophical issues of morality aside for now:

1) You began by saying the phrase "Christ died for our sins" signifies Penal Substitution

Yes. I was referring to 1 Corinthians 15:3. Penal substitution contains two ideas:

1) Someone is punished for some wrongdoing, i.e. endures a penalty (it's penal!)

2) That punishment is endured on behalf of another (it's substitutionary).

When Paul says "Christ died for our sins", it fulfills both criteria:

 
1) His death was specifically for sins - i.e. it was penal

2) His death was not for his own sins, but for ours - i.e. it was substitutionary

So there it is. But if I was making a full case, I'd go to many other even more direct Scriptures such as 1 Peter 3:18, "For Christ also has once suffered for sins, the just for the unjust" or 2 Peter 2:24, "Who his own self bare our sins in his own body on the tree, that we, being dead to sins, should live unto righteousness: by whose stripes you were healed" or Galatians 3:13, "Christ has redeemed us from the curse of the law, being made a curse for us". If those verses don't contain the very definition of a penal substitution, then I think words have no definite meaning.

, but note what 1 John 3:16 says:

"Jesus Christ laid down his life for us. And we ought to lay down our lives for our brothers."
Notice the parallelism here, if "lay down life for" means a PSub framework, the second half wouldn't make sense; it would be calling Christians to be Penal Substitutes for other Christians.Thus, saying "Christ died for our sins" and other such phraseology does not indicate Psub but instead put the burden on oneself to correct a problem, in a similar sense the way a father takes the burden of providing for his family on his shoulders (1 Tim 5:8).

This is multiple misunderstanding.

1) It is a grammatical error - you imply that "for" (Greek, huper) must carry a single meaning in all contexts. (Which you say, because it can't be "on account of" in 1 John 3:16, must therefore be "in order to help correct the problem of" because that meaning fits there). This is a lexical novelty and you won't find it taught in any Greek language resource.
"For" does not carry a unique meaning in English either. Prepositions simply don't work like this in any language I know. "I played for England", "I died for lack of water" and "I took a bullet for Fred" are three different meanings. To insist that "for" must mean the same in each sentence is gratuitous.

2) Secondly, I never intended to imply that penal substitution was implied simply by the word "for". As explained above, its the context that fixes the meaning. The word "for" in this context carries the meaning of "because of, on account of". But in the context of Scriptural theology, the only way that someone dies on account of sin is because death is a punishment for sin - the wages of sin is death. Hence later in the same chapter of 1 Corinthians 15 (verse 17) Paul states that if Christ did not do this, then you are still in your sins and (verse 18) will perish. Why do people perish because of sins? Only one reason: they are being punished for them. Moreover, the alternatives are absurd. Yours doesn't work - you make "for our sins" to mean "for us, to help us with our sins", changing the object of "for" from an impersonal entity (sins) into a person (us, who need help). This is rewriting the verse instead of learning from it.

2) You mentioned the scapegoat was an example of Penal Substitution, but the fact is the scapegoat was never killed, in fact it was set free (i.e. kept alive)!

You're confused here. If I'd said "the scapegoat is an example of a penal substitutionary death" then you'd have a point. But "penal substitution" simply means 1) penalty 2) substitution. The scapegoat was an example of these things, even though it did not die. Your thought here would ultimately rule out all teaching in advance by God to symbolically represent Christ's penal substitution, because the only thing that would exactly match all the details is the event itself!

3) You stated that hell was the primary punishment for sin, but using Penal Substitution means Jesus had to undergo hellfire in your place. The Bible simply nowhere teaches this, nor does it fit Trinitarian orthodoxy.

This is an arbitrary and unjustified assertion. Penal substitution does not mean that the suffered must experience precisely the same experience; it simply means that they must suffer a penalty of equivalent value. When the Kenyan government found my burglar guilty, they didn't sentence him to having the precise same items stolen from his own house - that would be impossible. Instead, they sentenced him to what they considered an equivalent punishment (ended up being 8 weeks in jail, since you ask).

4) Nowhere in the Bible is there a model for transferring punishment either in the Mosaic Law or in other cases of the atonement.

Well, we've been discussing one - the scapegoat. If there was no (symbolic, typical) transfer of guilt onto the scapegoat, then these verses have no meaning:

Leviticus 16:21 And Aaron shall lay both his hands upon the head of the live goat, and confess over him all the iniquities of the children of Israel, and all their transgressions in all their sins, putting them upon the head of the goat, and shall send him away by the hand of a fit man into the wilderness: 22 And the goat shall bear upon him all their iniquities unto a land not inhabited: and he shall let go the goat in the wilderness.

Hands are laid on the goat, symbolising transfer of sin. He is then said to go away outside the camp (into the wilderness), bearing the iniquities. If that's not transfer, then there must be no such thing as  transfer.

Consider the sin offering in Leviticus, note especially 5:11 where an animal could not be provided for the sin offering so a sack of flour was used instead. That is impossible if Psub were the framework, for you cannot kill a bag of flour. Further, the sin offerings were made for sins which did not require the death penalty, thus a 'life for life' model would not make sense.

Here you're attacking a strawman. Nobody claimed that every sacrifice in the Bible was penal and substitutionary.

As for turning away God's wrath and making atonement, the Bible gives many solid examples of where a hero turns away God's wrath and makes atonement without recourse to Psub (i.e. the hero getting punished in their place), consider:
-Num 25:1-13 (Ps 106:30-31);
-Deut9:16-21 (Ex 32:30,Psalm 106:19-23);
-Numbers 16:42-49
-Proverbs 16:6 says: “Through love and faithfulness sin is atoned for,” and 16:14 says, “A king's wrath is a messenger of death, but a wise man will appease it.”

All such examples are in principal moot. Read Romans 3:25-26, which explains that all the forgiveness given under the Old Testament era was predicated upon the future death of Christ, by which God could then be just. Without a death, it seemed (according to Romans 3:25-26) that God had passed over sin and left it unpunished.

But in any case, none of these sections establish your point. In Numbers 25 Phinehas slays the sinner. Likewise in Exodus 32 at the golden calf, the Levites go out to slay the evildoers. In Numbers 16, lots of people die in a plague - and it is stopped using implements from the tabernacle which are typical of the work of Christ; thus none of these prove that no penalty need be inflicted. Surely you're not seriously suggesting that Proverbs 16:6 and 14 are intended by the author as statements about the wiping away of a man's sin before God? That's torturing verses, not reading them.

What I've learnt from this Nick is that you don't like the idea of penal substitution. Of course you don't; nobody does. It implies that we're so sinful in God's sight that we can't save ourselves - the only remedy is as drastic as the Messiah suffering in our place. That's the humiliating truth of the gospel, and why you need to be born again - to accept God's verdict against you, and then to receive penal substitution not as a humiliation to be fought against, but as a saving truth in which we receive the love of God for all eternity.