This is one of my Dad’s notes I found in one of his books.
I have not found this quote in context but was able to find an article written by Bacchiocchi. From that article:
The free offering of time to God is a supreme act of worship, because it means acknowledging God with the very essence of human life: time. Life is time. When “time is up” life ceases to be. The offering of the Sabbath time to God enables the believer to acknowledge that his whole life, not just one seventh, belongs to God. It represents the Christian’s response to God’s claim on his life. By bringing all routine work to a halt for one day, he acts out his commitment to the Lord of his life. A similar objective is accomplished through the return of the tithe to God, as a recognition of His ultimate ownership.