Jamieson, Fausset and Brown on Isaiah 61:10

10. Zion (Is 61:3) gives thanks for God's returning favor (compare Lu 1:46, 47; Ha 3:18).

salvation ... righteousness--inseparably connected together. The "robe" is a loose mantle thrown over the other parts of the dress (Psa 132:9, 16; 149:4; Re 21:2; 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 (Ex 19:6; Re 5:10; 20:6).

jewels--rather, "ornaments" in general [Barnes].