The metaphor that Winthrop uses largely reflect the early Jewish people. He makes parallels between this colony being a new Jerusalem and this being a sort of call to Zion. He is using Typology of his day to make the connections. He proposes that the puritans are not being the best Christians they could be, and he thinks as god's chosen people it is up to them to live by example and commit to gods word. He equates the puritans needing to be some sort of powerful godly example.

Self sustained increase sounds good in comparison to the Spanish plantation approach of claiming a section of land and its inhabitants. It is almost creepy in a way that it seems a little fascist that would breed a group of people out of existence. Too I can see why the puritans were all about this approach especially since they clearly had something against the native peoples claiming them to be savages, and the bible has a popular scripture on the topic of having lots of children. May your quiver always be full the saying goes. I dislike this approach too for the reason it reminds me of germs. The people came to the land and immediately started breeding taking up land rapidly multiplying. I just couldn't imagine just walking into someones house and growing a family of my own in their until the one in residence had left.

The Author seems to be making the parallel between doing for each other what Jesus did for us. He promotes the idea of fidelity and kinship. He really digs into the idea of hardship and stating that this world is not the one god promised so it is filled with wretched things and as children of god we must endure hardship together and what I think he is saying here is along the lines of God will shelter us through the storm. There's an eternal promise, and part of me thinks he can usher in this world in this lifetime.