How long was mankind in God's day 6, how long in God's day 7, is God's day 7, salvation day for mankind?

Salvation belongs to the Lord. Psalm 3

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8Salvation belongs to the Lord; May Your blessing be upon Your people. Selah [pause, and calmly think of that]! Jonah 2

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9But as for me, I will sacrifice to You with the voice of thanksgiving; I will pay that which I have vowed. Salvation and deliverance belong to the Lord! 2 Peter 3

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8Nevertheless, do not let this one fact escape you, beloved, that with the Lord one day is as a thousand years and a thousand years as one day. Matthew 1

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21She will bear a Son, and you shall call His name Jesus [the Greek form of the Hebrew Joshua, which means Savior], for He will save His people from their sins [that is, prevent them from [a]failing and missing the true end and scope of life, which is God]. Exodus 20

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8[Earnestly] remember the Sabbath day, to keep it holy (withdrawn from common employment and dedicated to God). 11For in six days the Lord made the heavens and the earth, the sea, and all that is in them, and rested the seventh day. That is why the Lord blessed the Sabbath day and hallowed it [set it apart for His purposes]. 12Six days you shall do your work, but the seventh day you shall rest and keep Sabbath, that your ox and your donkey may rest, and the son of your bondwoman, and the alien, may be refreshed.

Romans 13

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11Besides this you know what [a critical] hour this is, how it is high time now for you to wake up out of your sleep (rouse to reality). For salvation (final deliverance) is nearer to us now than when we first believed (adhered to, trusted in, and relied on Christ, the Messiah).

1 Peter 1

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5Who are being guarded (garrisoned) by God's power through [your] faith [till you fully inherit that [a]final] salvation that is ready to be revealed [for you] in the last time.

Exodus 15

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2The Lord is my Strength and my Song, and He has become my Salvation; this is my God, and I will praise Him, my father's God, and I will exalt Him.

The Sabbath, or seventh day is the time given for the rebellion against the Almighty's creation to play out, and for the Kingdom of God to flourish.