I thought I'd switch with Friday's Paul post, since I'm working on getting through Philip Jenkins' Next Christendom at the same time the Contexts of Ministry class does.
So here is a second installment of chapter 2 of my writing project, Life Reflections on Paul's Writings. The first installment of the chapter is here.
... Paul at some point became a Pharisee. Perhaps his family, even though out in the Diaspora, maintained some connection with Jerusalem. Perhaps he moved to Jerusalem to reconnect with that "Hebrew of Hebrews" part of his past. He begins to study with Pharisees.
Acts 22:3 says that Paul was instructed at the feet of Gamaliel. Does Acts mean that Paul apprenticed as a Pharisee with Gamaliel? We know of two principal "schools" of Pharisee at this time, the school of Hillel and the school of Shammai. Jewish tradition came to consider this Gamaliel to be the grandson of Hillel and thus a "Hillelite." 
Paul's own descriptions of his pre-Christian self, however, sound more like a Shammaite than a Hillelite.  Gamaliel's speech in Acts 5 sounds exactly like a Hillelite. He argues fatalistically. God will take care of the situation. The Sanhedrin need not take any action against the apostles, because God will sort it out.
This is not Paul's approach, to say the least. Paul seems to have served the Jewish ruling council in Jerusalem, the Sanhedrin, in tracking down and arresting certain Christians. The apostles themselves do not seem to have been the target of Paul's persecutions. It was rather Greek speaking Jews like Stephen and Philip that seem to have been Paul's targets. It is quite possible that their understandings of Christ were more radical than those of the Aramaic speaking believers in Jerusalem. We notice that when the Hellenists were scattered in Acts 8, the apostles are able to stay put (Acts 8:1).
It has been very convenient to stereotype the Pharisees as hypocritical legalists, and quite possibly many were. This is certainly the dominant picture that we get from the Gospel of Matthew. Matthew 23 is a major critique of Pharisees who do not practice what they preach. Matthew tells its audience that the Jews should obey the Pharisees because of their authority as the bearers of Mosaic authority (23:2). But it criticizes them for not following their own teaching (23:3).
At the same time, we should bear in mind that the other gospels are not as harsh or dismissive, especially Luke-Acts. It has long been suggested that Matthew might present the Pharisees more starkly because they were hostile and in power at the time this gospel was written in the days after the destruction of Jerusalem. By contrast, Acts 15:5 speaks of Christian Pharisees and 23:6 calls Paul a Pharisee in the present tense. Thus Luke-Acts does not seem to view Pharisees as so diametrically opposed to believers.
We cannot be entirely sure of the origins of the Pharisees, although they clearly emerged in the mid-second century BC. Some consider them the heirs of the hasidim or faithful ones of the Maccabean revolt, individuals who chose to die rather than battle on the sabbath. Their name perhaps means something like "separated ones." Perhaps the goal was to keep the Jewish Law so well that God would restore Israel as a nation and usher in a golden age.
We thus need to make a careful distinction between someone who is very strict or detailed in their lifestyle and legalism. Legalism is when a person likes rules simply because a person likes rules, rules for their own sake. But someone might also live a strict life out of genuine devotion to God. We would be wrong to call such a person a legalist. Surely numerous Pharisees fell into this category, individuals like Nicodemus who lived a strict life out of true devotion to God.
It is hard to know what Paul's motivation was in persecuting these early believers. Did he think that by his zealous acts he was working toward the political restoration of Israel? Psychologically was he battling a stereotype someone might have made of him, a certain kind of "liberal," Greek speaking Jew that others might at some point have accused him of being? What exactly was it about the Hellenistic believers that he found so threatening in particular?
We do not know the answers. For example, did Paul himself detest believers for theological reasons but have authority to arrest for political reasons? Did some in power consider Hellenistic Christians subversive to their authority? It does not seem likely we will know the answers to these questions while we are on earth.
 It is the nature of tradition to make connections of this sort, to take what little is known of the past and connect it. A Clement in Philippians 4 might be connected to a Clement in Rome fifty years later, simply because in what little has survived from that time two people had the same name. We simply do not have sufficient evidence to know whether Gamaliel was truly the grandson of Hillel or not.
 One finds an excellent treatment of these issues in N. T. Wright's, The New Testament and the People of God, (Minneapolis: Fortress, **), **. And to give a third book of fifty to read on a path to master Paul, a great introduction is Wright's What Saint Paul Really Said (Grand Rapids: Eerdmans, **).