Bible Dictionary
FOURFOLD
Fourfold means four times the amount. In the cited passages it describes an extreme restitution for theft, while other laws required double restitution, an added fifth, or equal repayment.
Biblical Usage
David declares that the stolen lamb should be restored fourfold, and Zacchaeus promises fourfold restoration for wrongful exaction. The fourfold repayment is identified as the extreme penalty imposed by the law for theft.