Acts 2:44

And the class of oblations in general has not been set aside; for there were both oblations there [among the Jews], and there are oblations here [among the Christians]. Sacrifices there were among the people; sacrifices there are, too, in the Church: but the species alone has been changed, inasmuch as the offering is now made, not by slaves, but by freemen. For the Lord is [ever] one and the same; but the character of a servile oblation is peculiar [to itself], as is also that of freemen, in order that, by the very oblations, the indication of liberty may be set forth. For with Him there is nothing purposeless, nor without signification, nor without design. And for this reason they (the Jews) had indeed the tithes of their goods consecrated to Him, but those who have received liberty set aside all their possessions for the Lord's purposes, bestowing joyfully and freely not the less valuable portions of their property, since they have the hope of better things [hereafter]; as that poor widow acted who cast all her living into the treasury of God.

"And all that believed were together, and had all things common." Consider what an advance was here immediately! For the fellowship was not only in prayers, nor in doctrine alone, but also in social relations. "And sold their possessions and goods, and parted them to all men, as every man had need." See what fear was wrought in them! "And they parted them," he says, showing the wise management: "As every man had heed." Not recklessly, like some philosophers among the Greeks, of whom some gave up their land, others cast into the sea great quantities of money; but this was no contempt of riches, but only folly and madness. For universally the devil has made it his endeavor to disparage the creatures of God, as if it were impossible to make good use of riches.

"And all that believed were together, and had all things in common," etc. They are all become angels on a sudden; all of them continuing in prayer and hearing, they saw that spiritual things are common, and no one there has more than other, and they speedily came together, to the same thing in common, even to the imparting to all. "And all the believing," it says, were together: and to see that this does not mean that they were together in place, observe what follows "And had all things common". "All," it says: not one with the exception of another. This was an angelic commonwealth, not to call anything of theirs their own. Forthwith the root of evils was cut out.

Once more, the unanimity, the charity, which is the cause of all good things!

...now mortifying the earthly cravings of the old man, and inflamed with the new experience of the spiritual life, as the Lord had enjoined in the Gospel, they sold all that they had, and laid the price of their possessions at the feet of the apostles, in order that these might distribute to every man according as each had need; and living in Christian love harmoniously with each other, they did not affirm anything to be their own, but they had all things in common, and were one in soul and heart toward God. Afterwards these same persons also themselves suffered persecution in their flesh at the hands of the Jews, their carnal fellow-countrymen, and were dispersed abroad, to the end that, in consequence of their dispersion, Christ should be preached more extensively, and that they themselves at the same time should be followers of the patience of their Lord. For He who in meekness had endured them, enjoined them in meekness to endure for His sake.

As for selling and distributing their possessions according to whatever need one had, not merely, but in an economical manner. For they distributed according to value.

And they had all things in common, etc. If the love of God is poured into our hearts, it soon surely generates love for our neighbor. Hence, on account of the double ardor of charity, the Holy Spirit is read to have been given twice to the apostles. It is also a great indication of fraternal love to possess all things in common, having nothing as one's own.

"All… the believers were together," that is, not in place, but in disposition and in thoughts, in constant agreement among themselves and in love.