Acts 4 is a witness to the missional beliefs of Peter and the earliest Christians, and to helps us in this reading, we are reading The Acts of the Apostles (Abingdon New Testament Commentaries). The missional work of God establishes the missional community of God. Notice what happens as a result of witness to resurrection and filling with the Spirit:

All the believers were
one in heart and mind. No one claimed that any of his possessions was
his own, but they shared everything they had. With great power the apostles continued to testify to the resurrection of the Lord Jesus, and much grace was upon them all. There
were no needy persons among them. For from time to time those who owned
lands or houses sold them, brought the money from the sales and put it at the apostles’ feet, and it was distributed to anyone as he had need.

The mission work of God is to create communities that are at one in Christ. (See our Bonhoeffer posts from this week, but this unity is observed often by Gaventa with illuminating cross references.)

1. There is an economical responsiveness to one another. This is the emphasis of this paragraph, and economic responsiveness to one another is a hallmark of the Spirit’s presence. The emphasis is on the wealthy helping the poor, and I see no reason to think they surrendered ownership to the group; instead, there was individual ownership combined with willing commitment to others.
2. Their gospel is the resurrection of Jesus Christ. [It is this emphasis in the early Christian gospeling that makes me at times uncomfortable with some of evangelicalism’s Good Friday Only gospel. Crucifixion, by all means, but not at the expense of total neglect of resurrection.]
3. The missional work of the earliest Christians was under the leadership of the apostles — who were the witnesses to Jesus and his resurrection.