Threescore and ten thousand that bare burdens - These were all strangers, or proselytes, dwelling among the Israelites; as we learn from the parallel place, 2 Chronicles 2:17, 2 Chronicles 2:18.
That bare burdens - Compare the marginal references. These laborers, whose services were continuous, consisted of “strangers” - “the people that were left of the Amorites, Hittites, Perizzites, Hivites, and Jebusites” - whom Solomon, following the example of his father 1 Chronicles 22:2, condemned to slavery, and employed in this way.