'Empty' in the Bible

And they said, If ye send away the ark of the God of Israel, send it not empty; but in any wise return him a trespass offering: then ye shall be healed, and it shall be known to you why his hand is not removed from you.

You should not turn aside after empty things that can't profit and can't deliver, since they are empty.

Then Jonathan said to David, To morrow is the new moon: and thou shalt be missed, because thy seat will be empty.

And the king sat upon his seat, as at other times, even upon a seat by the wall: and Jonathan arose, and Abner sat by Saul's side, and David's place was empty.

And it came to pass on the morrow, which was the second day of the month, that David's place was empty: and Saul said unto Jonathan his son, Wherefore cometh not the son of Jesse to meat, neither yesterday, nor to day?