Exodus 30:16

And thou shalt take the atonement money of the children of Israel, and shalt appoint it for the service of the Tabernacle of the Congregation, for the perpetual service of God in the building devoted to His worship; that it may be a memorial unto the children of Israel before the Lord to make an atonement for your souls. They were ever to be reminded of the fact that they owed their souls to the Lord, that they were in His debt to the extent of their souls: in this sense the assessment was a ransom, money paid in atonement. To this day the Christians give evidence of the thankfulness of their hearts to God for the perfect atonement which was assured to them through Jesus Christ, also through their gifts and sacrifices.