One change that Puritan leaders worried about was the increase in material wealth among people in New England. This, it was thought, led to a more worldly outlook that had compromised the Puritan ideal. Another factor was the loosening of standards for full church membership. Puritans had traditionally required their full members to people who could claim a "conversion experience" and their children. With the passage of the so-called "halfway covenant," people who had not testified to such an experience could be admitted and could have their children baptized in the church, though they could not participate in communion. This, it was thought, encouraged a spirit of religious apathy or comfort. Another factor many blamed on declining religiosity was the outbreak of brutal Indian wars on the frontier, especially those that took place during King William's War in the late seventeenth century. Many saw this as a sign that the Puritans had lost the favor of God. Each of these concerns made New England fertile ground for a religious revival in the early eighteenth century.