No sin was worse than that of the usurer, no activity more repugnant to the Lord. The objection to the presence of commerce and banking in early medieval times was spearheaded by the clergy, who thundered against the sinful nature of their calling. Although medieval society increasingly came to rely upon the merchant's services in distributing and obtaining items not produced locally, he was nonetheless considered a parasite and a sinner, barely tolerated for his questionable contribution to society's output. His pursuit of gain was considered against the laws of God, because he was not a producer of real goods, but rather a resaler, or a usurer. The merchant, as a class, was discriminated against for not contributing to these essential duties, but rather for aiming to get rich himself. Each of these groups had a role to play, either defense of the realm, maintenance of the soul of society, or the growing of essential foodstuffs. The old, feudal model of society was dominated by the concept that there were three divinely ordained orders: knights, clergy, and peasants. Boccaccio reflects these changes in several of his novellas, as he portrays merchants as victims of the times, and also as heroes on the forefront of social change. All of this, combined with the Church's criticism of commerce and usury, created a multi-layered complex of attitudes towards those who made their living by buying and selling goods or dealing with money. The merchant himself changed in his attitude towards his work, in his duties and abilities, and in his educational background. Changing attitudes towards trade and the merchant class marked this period. The 13th and 14th centuries saw a tremendous growth in commercial activity, and a consequent restructuring of society, away from the feudal system. Societal Structure and the New Urban Economy.