The famous German economist, Max Weber, proposed the connection between Calvinism and Free Market labor almost one-hundred years ago.
Echoing Weber’s thesis, book reviewer, CARL ROLLYSON, opines:
"The Calvinist did not know if he was one of the elect or the damned [not necessarily true]. Good works might not save him, but good works were necessary as part of his own effort to convince himself that he deserved election. It was the extraordinary drama of not knowing one's ultimate fate that drove Calvinists to create just and equitable societies for themselves and for others. In other words, at every turn what the individual did was up to him. This is a hugely liberating psychology that did indeed lead (ironically) to a sense of selfhood that ultimately doomed Calvinism. And yet, without Calvin, it is difficult to see how the secular notion of individual liberty could have flourished." [The New York Sun, The Calamity of Selfhood, By July 19, 2006 ]
Although her analysis is a simplification of the true doctrinal basis of good works in the Calvinist system (out of gratitude), she, as others, admits to the overall positive effect of Calvinism.
Furthermore, the Reformers allowed the use of interest for money and the accumulation of wealth for families and their children’s children.This further stimulated capitalism.
Again, since the kingdom of God was wherever the Christian’s vocation in life was, those lawful activities of work and recreation were sanctified unto God.It was not sinful per se to accumulate wealth nor seek after prosperity.Although, given no biblical guarantee of prosperity (see Job), the believer knew that the biblical ideals of hard work and thrift generally lead to plentitude. And in the spirit of true mercy, the office of the deacon flurished in the Reformed churches as well, helping those in economical need.