Hence, if men are in Prosperity, the Devil will tempt them to Forgetfulness of God; if they are in Adversity, he will tempt them to Murmuring at God; in all the expressions of those impieties. Wise Agur was aware of this; in Prov. 30.9. says he, if a man be Full, he shall be tempted, to deny God, and say, who is the Lord? if a man be Poor, he shall be tempted, to steal, and take the Name of God in vain. The Devil will talk suitably; if you ponder your Conditions, you may expect you shall be tempted agreeably thereunto.
Cotton uses the bible in a different way here. He explains how God will tempt anyone and everyone. And I believe that he points this out because during this time people thought that if they followed their preacher, practiced good religion, and fully believed in God they wouldn’t be affected by the devil at all. I think that by Cotton expressing this it had a big impression on the community.