They formed private communities, like monasteries, and pooled their resources. The key was that they were not forced or coerced by a government agency. Nor, did they in their entire 2000+ years create a government - small or large - that forced or coerced their members to pool their resources. The members of these private communities were voluntary members who accepted the rule of the private community voluntarily. Not all their private communities where based on pure socialistic pooling principles. Some allowed for profits. One thing that was consistent with their solidarity (all for all) was their subsidiarity (at the most appropriate local level). With a small community, there was something that could be more readily administered - accountability. They knew where you lived. They knew where their resources were going. They could track transactions.
Capitalism & socialism has similar end products - mo’ money, yo’ money.
Big government & big corporations where money is laundered, manipulated, co-mingled, and hidden under tax shelters are the real enemies of society.
Smaller government & smaller corporations, where you know your neighbors & know what you are doing to your neighbors, are the real solution.
And, the smallest unit of all must be held sacred and nurtured & cultivated to good health - marriage & family.