42 And they devoted themselves to the apostles' teaching and the fellowship, to the breaking of bread and the prayers. 43 And awe came upon every soul, and many wonders and signs were being done through the apostles. 44 And all who believed were together and had all things in common.45 And they were selling their possessions and belongings and distributing the proceeds to all, as any had need. 46 And day by day, attending the temple together and breaking bread in their homes, they received their food with glad and generous hearts, 47 praising God and having favor with all the people. And the Lord added to their number day by day those who were being saved. ~ Acts 2:42-47
Well actually this passage does not provide a foundation for socialism, Christian or otherwise. As Ludwig von Mises explained in his great work Socialism, at most the early Christians in Jerusalem practiced a socialism of consumption and not production. In actuality there was not even socialism of consumption if by that we mean that all of their consumable property was owned collectively. Notice that in verse 45 they were selling their own property and then distributing the proceeds.
Additionally, as was explained noted in a recent Sunday School class by one of our church's elders, who also holds a PhD in ancient history, from verse 43 to the end of the chapter, the language becomes descriptive and not proscriptive. In other words, this was Luke writing history without saying that all Christians must do exactly the same. Of course the diaconal ministry was instituted later to satisfy the very needs that were being satisfied by individual church members described in Acts 2. While the early Christians in Jerusalem do serve as excellent examples of Christian charity, such charitable sharing and giving away our own property is a far cry from socialism as an economic system.
As Matthew Henry explains in his commentary on Acts 2:42-47,
The greatness of the event raised them above the world, and the Holy Ghost filled them with such love, as made every one to be to another as to himself, and so made all things common, not by destroying property, but doing away selfishness, and causing charity.