2 Nephi 8

As we contemplate the words "arm of the Lord", in my mind it would suggest his omnipotent power. and yet at the same time,we realize that he always seems to do His work through righteous men and women or through His priesthood. So as I read the prophecies of Isaiah in the last days, I found a duel meaning as he wrote -

"Awake, awake! Put on strength, O arm of the Lord; awake as in the ancient days..." (Book of Mormon | 2 Nephi 8:9)

Isaiah then follows with a reflection on how the arm of the Lord was revealed anciently. You can sense an appeal that the Lord bare his holy arm in these days as well as an appeal that the righteous also step forward and be the instruments of the Lord as in ancient days such as Moses.

Then there is an appeal for Israel (who has not always remained faithful) to step up and be worthy in our day and to do so saying -

"...unto Zion: Behold, thou art my people [or covenant people].
17 Awake, awake, stand up, O Jerusalem, which hast drunk at the hand of the Lord the cup of his fury—thou hast drunken the dregs of the cup of trembling wrung out—..." (Book of Mormon | 2 Nephi 8:16 - 17)

The very definition of Zion -

"...is Zion—THE PURE IN HEART..." (Doctrine and Covenants | Section 97:21)

or in other words, a people -

"...because they were of one heart and one mind, and dwelt in righteousness; and there was no poor among them." (Pearl of Great Price | Moses 7:18)

In our days, as in the days of Enoch, the saints are to -

"Awake, awake, put on thy strength, O Zion; put on thy beautiful garments, O Jerusalem, the holy city [or city of Zion]..." (Book of Mormon | 2 Nephi 8:24)

In my mind, beautiful garments are the white garments of purity, righteousness, and holiness. Awake and step up.