'Thing' in the Bible

The son of Carmi: Achar, the troubler of Israel, who acted unfaithfully in the matter of the devoted thing.

So now, O Yahweh, you yourself [are] God, and you have spoken to your servant this good thing.

Then David said to God, "I have sinned severely [in] that I have done this thing. But now, please forgive the sin of your servant, for I have been very foolish."