what is the reason behind it?
The new settlers had different religious views than Winthrop according to whom , these beliefs were heresy.
John Winthrop
In 1634 and 1635, Winthrop served as an assistant, while the influx of settlers brought first John Haynes and then Henry Vane to the governorship. Haynes, Vane, Anne Hutchinson, and pastors Thomas Hooker and John Wheelwright all espoused religious or political views that were at odds with those of the earlier arrivals, including Winthrop. Hutchinson and Wheelwright subscribed to the Antinomian view that following religious laws was not required for salvation, while Winthrop and others believed in a more Legalist view. This religious rift is commonly called the Antinomian Controversy, and it significantly divided the colony; Winthrop saw the Antinomian beliefs as a particularly unpleasant and dangerous heresy. By December 1636, the dispute reached into colonial politics, and Winthrop attempted to bridge the divide between the two factions. 
who was the original leader of the puritans in the colonies and what was his famous quote John Winthrop. His quote was "bear one another's burdens". who was he? An English Puritan lawyer. was he a writer? Yes. can you name some of his works? : "A Modell of Christian Charity" and "The History of New England". was he involved in any controversy? Yes, the Antinomian controversy.
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John Winthrop [SEP] Religious controversies
By December 1636, the dispute reached into colonial politics, and Winthrop attempted to bridge the divide between the two factions. He wrote an account of his religious awakening and other theological position papers designed to harmonize the opposing views. (It is not known how widely these documents circulated, and not all of them have survived.) In the 1637 election, Vane was turned out of all offices, and Dudley was elected governor. Dudley's election did not immediately quell the controversy. First John Wheelwright and later Anne Hutchinson were put on trial, and both were banished from the colony. (Hutchinson and others founded the settlement of Portsmouth on Rhode Island; Wheelwright founded first Exeter, New Hampshire and then Wells, Maine in order to be free of Massachusetts rule.) Winthrop was active in arguing against their supporters, but Shepard criticized him for being too moderate, claiming that Winthrop should "make their wickedness and guile manifest to all men that they may go no farther and then will sink of themselves." Hooker and Haynes had left Massachusetts in 1636 and 1637 for new settlements on the Connecticut River (the nucleus of the Connecticut Colony); Vane left for England after the 1637 election, suggesting that he might seek a commission as a governor general to overturn the colonial government.