'Themselves' in the Bible

“Many nations will join themselves to the Lord in that day and will become My people. Then I will dwell in your midst, and you will know that the Lord of hosts has sent Me to you.

And I answered the second time and said to him, “What are the two olive branches which are beside the two golden pipes, which empty the golden oil from themselves?”

The land will mourn, every family by itself; the family of the house of David by itself and their wives by themselves; the family of the house of Nathan by itself and their wives by themselves;

the family of the house of Levi by itself and their wives by themselves; the family of the Shimeites by itself and their wives by themselves;

all the families that remain, every family by itself and their wives by themselves.