Responses on the Spirit

It looks like the main issues in question are:

1. The Spirit in the Old Testament
2. The role of the "sign gifts"
3. The nature of "baptism of the Spirit"

1. The Spirit in the OT

The entire Old Covenant economy was different from the New as it relates to the Spirit in the lives of God's people. Joel 2 (which Peter quotes at Pentecost) is seen as foreseeing a fundamentally New Covenant reality: "And in the last days it shall be, God declares, that I will pour out my Spirit on all flesh..." (Joel 2:28; Acts 2:17). Under the Old Covenant the people had the law written upon tablets of stone, but in the New it is written on hearts of flesh. I agree with Ben's point: in 2 Corinthians 3, Paul's whole point is that the New Covenant is superior to the Old, more glorious and un-veiled -- and the fundamental difference between them is the presence of the Spirit in the New Covenant!

Similarly, John 7:37-39 says: "In the last day of the feast, the great day, Jesus stood up and cried out, 'If anyone thirsts, let him come to me and drink. Whoever believes in me, as the Scripture has said, "Out of his heart will flow rivers of living water."' Now this he said about the Spirit, whom those who believed in him were to receive, for as yet the Spirit had not been given, because Jesus was not yet glorified." The point here being that the giving of the Spirit (Pentecost) is directly related to the glorification of Jesus (post-Ascension).

2. The role of the "sign gifts"

I don't see Paul cutting a neat dichotomy between the "sign gifts" and the other gifts of the Spirit. In 1 Corinthians 12:7-10, I see the "sign gifts" -- healing, miracles, tongues, etc -- lumped together with other less "exciting" gifts -- utterances of wisdom and knowledge, faith, discernment. Similarly, in verses 27-31 Paul says: "Now you are the body of Christ and individually members of it. And God has appointed in the church first apostles, second prophets, third teachers, then miracles, then gifts of healing, helping, administrating, and various kinds of tongues. Are all apostles? Are all prophets? Are all teachers? Do all work miracles? Do all possess gifts of healing? Do all speak with tongues? Do all interpret? But earnestly desire the higher gifts. And I will show you a still more excellent way." Again, Paul lumps all kinds of gifts together, both "sign gifts" and mundane gifts, like helping and administrating.

Also, in 1 Cor 14:4 Paul says, "The one who speaks in a tongue builds up himself." Therefore, I think that the role of this gift can also be for private edification. Paul says further in that chapter (1 Cor 14:18-19): "I thank God that I speak in tongues more than all of you. Nevertheless, in church I would rather speak five words with my mind in order to instruct others, than ten thousand words in a tongue." Paul here directly contrasts speaking in tongues with what he does "in church." It seems that Paul here envisions tongues as a private gift, for his own personal edification. Surely, tongues were a public action of the Spirit in order to authenticate the Gospel (see Acts 2), but they were also, it seems clear from Paul's argument here, a private gift for personal edification.

3. The nature of "Spirit baptism"

Overall, I would say that the post-Pentecost baptisms of the Spirit took place at a very specific place in redemptive history, for a very specific purpose. Each occurs in the context of the Jerusalem-Judea-Samaria-ends of the earth framework of the whole book of Acts. I take these to be special, one-time events in which the Spirit is progressively given to all types of people -- Jews, Samaritans, Gentiles -- thereby in fulfillment of OT prophecy.

Also, Paul seems to clearly state in Eph 4:5 that there is "one baptism." The same applies to 1 Corinthians 12:13: "For in one Spirit we were all baptized into one body- Jews or Greeks, slaves or free- and all were made to drink of one Spirit." If there was a separate experientially related baptism of the Spirit, surely Paul would've mentioned it in this context. But instead he seems to relate the one-time baptism of all believers without exception, to the receiving and "drinking" of the one Spirit of God.

That's all for now.

As a side note:
I confess a certain amount of pride in my heart/desire to "win" as I write this. That's not the attitude I want to have, and not the attitude God desires for me. I want to sharpen and be sharpened. I also don't want to posture as falsely humble. I'm not. Forgive me for that.