Why did Winthrop write "A Model of Christian Charity"?
Winthrop's sermon, delivered on board the Arbella, was to admonish those who travelled with him that they were to establish a new community in the new world which was to be, in his words, "a city on a hill."
The eyes of all people are upon us, so that if we shall deal falsely with our God in this work we have undertaken, and so cause him to withdraw his present help from us, we shall be made a story and a by-word through the world: we shall open the mouths of enemies to speak evil of the ways of God and all professors for God's sake. We shall shame the faces of many of God's worthy servants, and cause their prayers to be turned into curses upon us, till we be consumed out of the good land whither we are going.
Winthrop and his fellow travellers referred to themselves as the "Godly," but were known in England as "Puritans," as they hoped to purify the Church of England and remove from it any element of "popery." Typical of the Puritans, they were convinced that they were right and everyone else was wrong in theological matters. Winthrop wanted the new colony in New England to be an example of what a Christian community should look like. If they succeeded, then the world would know that God was on their side; if they failed, then it was their own fault for having abandoned their principles.
Ironically, Winthrop, a lawyer, was himself hardly a model of christian charity. Upon departing for England, he managed to take the charter of the Massachusetts Bay Company with him, so the company had no headquarters in England. All company decisions were made in New England and largely controlled by Winthrop himself.