This may really upset the Anti-Sabbath proponents.
Verse By Verse Commentary - Studylight
"And it shall be from new moon to new moon And from sabbath to sabbath, All mankind will come to bow down before Me," says the LORD.
.....And from one Sabbath to another - (Compare the notes at Isaiah 58:13-14). There can be no permanent worship of God, and no permanent religion on earth, without a Sabbath; and hence it was, that while the observance of the feasts of tabernacles, and of the Passover, and of the new moons, made a part of the ceremonial law, the law respecting the sabbaths was incorporated with the ten commandments as of moral and perpetual obligation; and it will be literally true that all the race shall yet be brought to worship God on the return of that holy day.
It was instituted in paradise; and as one design of the plan of redemption is to bring man back to the state in which he was in paradise, so one effect of the true religion everywhere will be, and is, to make people reverence the Sabbath of the Lord. No man becomes truly pious who does not love the holy Sabbath. No nation ever has been, or ever can be converted which will not, and which does not, love and observe that day. Every successful effort to propagate the true religion is a successful effort to extend the practice of observing it; and just as certain as it is that Christianity will be spread around the world, so certain will it be that the Sabbath will be observed in all lands. The period is, therefore, yet to arrive when the delightful spectacle will be presented of all the nations of the earth bowing on the return of that day before the living God. The plans of this life will be suspended; toil and care will be laid aside; and the sun, as he rolls around the world, will rouse nation after nation to the worship of the true God; and the peace and order and loveliness of the Christian Sabbath will spread over all the hills and vales of the world. Who that loves the race will not desire that such a period may soon come? Who can wonder that Isaiah should have fixed his eye in the close of his prophetic labors on a scene so full of loveliness, and so replete with honor to God, and with goodwill to people?
Shall all flesh - All the human family, all nations - a most unequivocal promise that the true religion shall yet prevail around the world.
Come to worship before me - That is, they shall assemble for the worship of God in their respective places of devotion.