Beginning of the End - Ellen G. White

In no case should our own business be allowed to infringe on holy
time. God has directed that the sick should be cared for--the labor
required to make them comfortable is a work of mercy and not a
violation of the Sabbath, but all unnecessary work should be
avoided. Work that is neglected until the beginning of the Sabbath
should remain undone until after sundown at its close.
The Israelites witnessed a three-part miracle to impress their
minds with the sacredness of the Sabbath: a double quantity of
manna fell on the sixth day, none on the seventh, and the portion
needed for the Sabbath stayed sweet and pure.
Sabbath Before Sinai
In the way God gave the manna, we have undeniable evidence
that the Sabbath did not originate when the law was given at Sinai.
Before the Israelites came to Sinai they understood that God
expected them to keep the Sabbath. When every Friday they had to
gather a double portion of manna in preparation for the Sabbath, the
sacred nature of the day of rest was continually impressed upon
them. And when some of the people went out on the Sabbath to
gather manna, the Lord asked, "How long do you refuse to keep My
commandments and My laws?"
"The children of Israel ate manna forty years ... until they came
to the border of the land of Canaan." For forty years they were
reminded daily of God's unfailing care and tender love. God gave
them "of the bread of heaven. Men ate angels' food" (Psalm 78:24,
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