The Sabbath in the Age to Come

God created the Sabbath for mankind and there will yet come a time when all mankind will keep God's Sabbath.

God created the Sabbath for mankind (Mark 2:27And he said unto them, The sabbath was made for man, and not man for the sabbath:
See All...), and there will yet come a time when all people will keep God's Sabbath.

The Bible speaks of God's Kingdom as being established on earth when Jesus Christ returns to rule as "King of Kings and Lord of Lords" (Revelation 11:15And the seventh angel sounded; and there were great voices in heaven, saying, The kingdoms of this world are become the kingdoms of our Lord, and of his Christ; and he shall reign for ever and ever.
See All...; 19:11-16). In addition to ruling over sons of God who will be changed to spirit beings and rule with Christ in the Kingdom of God at the time of His second coming, Jesus will rule as Head of a literal government over physical nations on earth (Psalm 22:27-28 [27] All the ends of the world shall remember and turn unto the LORD: and all the kindreds of the nations shall worship before thee.
[28] For the kingdom is the LORD's: and he is the governor among the nations.

See All...; 72:1-11; Daniel 2:34-35 [34] Thou sawest till that a stone was cut out without hands, which smote the image upon his feet that were of iron and clay, and brake them to pieces.
[35] Then was the iron, the clay, the brass, the silver, and the gold, broken to pieces together, and became like the chaff of the summer threshingfloors; and the wind carried them away, that no place was found for them: and the stone that smote the image became a great mountain, and filled the whole earth.

See All...; Zechariah 14:8-9 [8] And it shall be in that day, that living waters shall go out from Jerusalem; half of them toward the former sea, and half of them toward the hinder sea: in summer and in winter shall it be.
[9] And the LORD shall be king over all the earth: in that day shall there be one LORD, and his name one.

See All...).

At that time, all nations will be ruled by God's laws (Jeremiah 31:31-34 [31] Behold, the days come, saith the LORD, that I will make a new covenant with the house of Israel, and with the house of Judah:
[32] Not according to the covenant that I made with their fathers in the day that I took them by the hand to bring them out of the land of Egypt; which my covenant they brake, although I was an husband unto them, saith the LORD:
[33] But this shall be the covenant that I will make with the house of Israel; After those days, saith the LORD, I will put my law in their inward parts, and write it in their hearts; and will be their God, and they shall be my people.
[34] And they shall teach no more every man his neighbour, and every man his brother, saying, Know the LORD: for they shall all know me, from the least of them unto the greatest of them, saith the LORD: for I will forgive their iniquity, and I will remember their sin no more.

See All...; Micah 4:2And many nations shall come, and say, Come, and let us go up to the mountain of the LORD, and to the house of the God of Jacob; and he will teach us of his ways, and we will walk in his paths: for the law shall go forth of Zion, and the word of the LORD from Jerusalem.
See All...; Isaiah 2:2-3 [2] And it shall come to pass in the last days, that the mountain of the LORD's house shall be established in the top of the mountains, and shall be exalted above the hills; and all nations shall flow unto it.
[3] And many people shall go and say, Come ye, and let us go up to the mountain of the LORD, to the house of the God of Jacob; and he will teach us of his ways, and we will walk in his paths: for out of Zion shall go forth the law, and the word of the LORD from Jerusalem.

See All...; Hebrews 8:7-13 [7] For if that first covenant had been faultless, then should no place have been sought for the second.
[8] For finding fault with them, he saith, Behold, the days come, saith the Lord, when I will make a new covenant with the house of Israel and with the house of Judah:
[9] Not according to the covenant that I made with their fathers in the day when I took them by the hand to lead them out of the land of Egypt; because they continued not in my covenant, and I regarded them not, saith the Lord.
[10] For this is the covenant that I will make with the house of Israel after those days, saith the Lord; I will put my laws into their mind, and write them in their hearts: and I will be to them a God, and they shall be to me a people:
[11] And they shall not teach every man his neighbour, and every man his brother, saying, Know the Lord: for all shall know me, from the least to the greatest.
[12] For I will be merciful to their unrighteousness, and their sins and their iniquities will I remember no more.
[13] In that he saith, A new covenant, he hath made the first old. Now that which decayeth and waxeth old is ready to vanish away.

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All of humanity will then learn and keep God's Sabbath: "'From one New Moon to another and from one Sabbath to another, all mankind will come and bow down before me,' says the Lord" (Isaiah 66:23And it shall come to pass, that from one new moon to another, and from one sabbath to another, shall all flesh come to worship before me, saith the LORD.
See All..., New International Version).

The Sabbath will be kept by gentiles and those who were never a part of the physical nation of Israel. "Thus says the Lord: 'Keep justice, and do righteousness, for My salvation is about to come, and My righteousness to be revealed. Blessed is the man who does this, and the son of man who lays hold on it; who keeps from defiling the Sabbath, and keeps his hand from doing any evil . . .

"To the eunuchs who keep My Sabbaths, and choose what pleases Me, and hold fast My covenant, even to them I will give in My house and within My walls a place and a name better than that of sons and daughters; I will give them an everlasting name that shall not be cut off.

"'Also the sons of the foreigner who join themselves to the Lord, to serve Him, and to love the name of the Lord, to be His servants—everyone who keeps from defiling the Sabbath, and holds fast My covenant—even them I will bring to My holy mountain, and make them joyful in My house of prayer'" (Isaiah 56:1-2 [1] Thus saith the LORD, Keep ye judgment, and do justice: for my salvation is near to come, and my righteousness to be revealed.
[2] Blessed is the man that doeth this, and the son of man that layeth hold on it; that keepeth the sabbath from polluting it, and keepeth his hand from doing any evil.

See All..., 4-7).

Sabbath observance is specifically mentioned as a part of the covenant God will make with all peoples then, and their worship of Him. It will be an important part of Jesus Christ's coming reign on earth!