Old South Church voted overwhelmingly on Sunday to let its trustees sell one of the church’s two copies of the 1640 Bay Psalm Book, the first book published in the British North American Colonies, a rare text that specialists say could fetch more than $10 million at auction.

The vote came after an impassioned but respectful discussion in which a few members entreated their fellow congregants not to part with such a treasure — at least not yet — but many more speakers declared that now was the time to solidify Old South’s finances and invest in its future.