From Alexander Schmemann, A History of the Orthodox Church

For the early Church, unity in love was the ultimate value; it was the supreme purpose of life that Christ Himself had revealed to men. …

This unity was demonstrated above all in the active love through which each Christian was conscious that he belonged to all the brethren, and conversely, that they all belonged to him. The unity of Christians with one another is now, alas, only symbolized by their communion in divine service; in the early Church the liturgy was the crowning point of a real unity, a continual communion in everyday life; moreover, the liturgy was then unthinkable apart from that communion. In early Christian writings no other word is so often repeated as “brother,” and Christians of that age filled the idea of brotherhood with vital meaning, which showed clearly in their unity of thought: “And the multitude of them that believed were of one heart and of one soul . . .” (Acts 4:32).

Brotherhood also meant active mutual support among Christians “of all for all” — a care which was both material and spiritual. “And all that believed were together, and had all things in common; and sold their possessions and goods, and parted them to all men, as every man had need” (Acts 2:44f.).

The very smallness of the Christian community in Jerusalem made it possible to put unity of life into practice in a radical way through sharing their property. This phenomenon, inaccurately described as “primitive Christian communism,” was not the product of any specifically Christian economic or social theory, but a manifestation of love. Its meaning lies not in community of property as such, but in the evidence it gives us of the new life that manifested itself among them, entirely transforming the old.