Isaiah 61:10

Some make this the song of joy and praise to be sung by the prophet in the name of Jerusalem, congratulating her on the happy change of her circumstances in the accomplishment of the foregoing promises; others make it to be spoken by Christ in the name of the New Testament church triumphing in gospel grace. We may take in both, the former as a type of the latter. We are here taught to rejoice with holy joy, to God's honour, 1. In the beginning of this good work, the clothing of the church with righteousness and salvation, Isa 61:10. Upon this account I will greatly rejoice in the Lord. Those that rejoice in God have cause to rejoice greatly, and we need not fear running into an extreme in the greatness of our joy when we make God the gladness of our joy. The first gospel song begins like this, My soul doth magnify the Lord, and my spirit hath rejoiced in God my Saviour, Luk 1:46, Luk 1:47. There is just matter for this joy, and all the reason in the world why it should terminate in God; for salvation and righteousness are wrought out and brought in, and the church is clothed with them.

— Matthew Henry's Concise Commentary (public domain)

Zion (Isa 61:3) gives thanks for God's returning favor (compare Luk 1:46-47; Hab 3:18). salvation . . . righteousness--inseparably connected together. The "robe" is a loose mantle thrown over the other parts of the dress (Psa 132:9, Psa 132:16; Psa 149:4; Rev 21:2; Rev 19:8). decketh himself with ornaments--rather "maketh himself a priestly headdress," that is, a magnificent headdress, such as was worn by the high priest, namely, a miter and a plate, or crown of gold worn in front of it [AQUILA, &c.]; appropriate to the "kingdom of priests," dedicated to the offering of spiritual sacrifices to God continually (Exo 19:6; Rev 5:10; Rev 20:6). jewels--rather, "ornaments" in general [BARNES].

— Jamieson-Fausset-Brown Commentary (public domain)