Jamieson, Fausset & Brown, on Neh 6:10

Afterward I came unto the house of Shemaiah, &c.--This man was the son of a priest, who was an intimate and confidential friend of Nehemiah. The young man claimed to be endowed with the gift of prophecy. Having been secretly bribed by Sanballat, he, in his pretended capacity of prophet, told Nehemiah that his enemies were that night to make an attempt upon his life. He advised him, at the same time, to consult his safety by concealing himself in the sanctuary, a crypt which, from its sanctity, was strong and secure. But the noble-minded governor determined at all hazards to remain at his post, and not bring discredit on the cause of God and religion by his unworthy cowardice in leaving the temple and city unprotected. This plot, together with a secret collusion between the enemy and the nobles of Judah who were favorably disposed towards the bad Samaritan in consequence of his Jewish connections (Neh 6:18), the undaunted courage and vigilance of Nehemiah were enabled, with the blessing of God, to defeat, and the erection of the walls thus built in troublous times (Dan 9:25) was happily completed (Neh 6:15) in the brief space of fifty-two days. So rapid execution, even supposing some parts of the old wall standing, cannot be sufficiently accounted for, except by the consideration that the builders labored with the ardor of religious zeal, as men employed in the work of God. Next: Nehemiah Chapter 7