Acts 2:44-47
44. All the believers were together and had everything in common.
45. Selling their possessions and goods, they gave to anyone as he had need.
46. Every day they continued to meet together in the temple courts. They broke bread in their homes and ate together with glad and sincere hearts,
47. praising God and enjoying the favor of all the people. And the Lord added to their number daily those who were being saved.
1 Timothy 5:8
If anyone does not provide for his relatives, and especially for his immediate family, he has denied the faith and is worse than an unbeliever.
Anytime a parishoner gives an offering "in excess" of their normal use (ie providing for their family) to their church for the sustenance of the poor, it is not socialism. This is not just Mornmons. A Baptist who donates time or money to their church's food bank is practicing the same biblical law. What is interesting is that just because mormons practice it as well some are willing to criticize them for it, even though it is in the Bible and practiced by many churches today.
Then of course there is the example of the widow and the prophet Elijah in the OT or the widow's mite from the NT. But that is another discussion.