Raising a bulwark means building up a wall for protection against the people who do not follow and practice the religion of Christianity.
Explanation:
John Winthrop was the one who got firer wave of a huge number of immigrants to New England.
And he wanted to establish a pure church in the region of New England was not in the favour of separatism.
And wanted to change New England in a puritan society and wanted to help each other and treat each other well.
