'Certain' in the Bible

Only know for certain that, if you put me to death, you will bring innocent blood on yourselves, and on this city, and on its inhabitants; for of a truth Yahweh has sent me to you to speak all these words in your ears.

Then rose up certain of the elders of the land, and spoke to all the assembly of the people, saying,

and Jehoiakim the king sent men into Egypt, [namely], Elnathan the son of Achbor, and certain men with him, into Egypt;