'Useful' in the Bible

Everyone making an offering of silver or bronze brought it as a contribution to the Lord. Everyone who possessed acacia wood useful for any task in the work brought it.

Can wood be taken from it to make something useful? Or can anyone make a peg from it to hang things on?

In fact, it is put into the fire as fuel. The fire devours both of its ends, and the middle is charred. Can it be useful for anything?

Even when it was whole it could not be made into a useful object. How much less can it ever be made into anything useful when the fire has devoured it and it is charred!