The necessity of charity is the most dominant theme of Winthrop’s sermon. Charity is a fundamental demand God places on humanity; it’s woven into the very structure of society and exemplified in God’s creation of wealth disparity so that “every man might have need of others” (34). This demand for charity appears in the moral law given to the Israelites, and “upon this ground stands all the precepts of the morrall lawe, which concernes our dealings with men” (34). This demand for charity, however, also appears with Christ’s coming and the delivery of the law of the Gospel. This law demands one to “Doe good to all, especially to the household of faith” (35). To Winthrop, charity is the single central Christian ideal, and those who do not practice charity as Christ intends are not true Christians, a belief Winthrop backs up with scripture: “John 1. he whoe hath this world's goodes and seeth his brother to neede and shutts upp his compassion from him, how dwelleth the loue of God in him?” (37).

Though God demands charity, he does not do so directly. Instead, he places love in the hearts of all people, to find its outward expression in charity.