Romans 8:19-21 — For the earnest expectation of the creature waiteth for the manifestation of the sons of God.
(For the creature was made subject to vanity, not willingly, but by reason of him who hath subjected the same) in hope,
Because the creature itself also shall be delivered from the bondage of corruption into the glorious liberty of the children of God.
Expectation — has the sense of craning the neck to look for something
Waiteth — stress on expectancy
Manifestation = revealing. When the Lord returns in glory (second coming), we too will come in His likeness. When Christ, who is our life, shall appear, then shall ye also appear with Him in glory (Colossians 3:4).
Sons of God (verse 19) — representing the Father's character and displaying His glory.
Children of God (verse 21) — in reference to adoption and heirship.
Vanity = void of good results, frail, unable to achieve the design of its being. Creation isn't accomplishing its purpose because it shares the curse on man for sin, due to the ruling providence of God.
In hope = sure of fulfillment. This is tied to the end of verse 19. The rest of verse 21 is a parentheses).
Delivered = made free (as in Romans 6:18,22; 8:2)
Corruption = decay and death
Liberty — Creation will share with men the freedom to fulfill the purpose it was created for.
Creation will rejoice: Make a joyful noise unto the LORD, all the earth: make a loud noise, and rejoice, and sing praise. Sing unto the LORD with the harp; with the harp, and the voice of a psalm. With trumpets and sound of cornet make a joyful noise before the LORD, the King. Let the sea roar, and the fulness thereof; the world, and they that dwell therein. Let the floods clap their hands: let the hills be joyful together Before the LORD; for He cometh to judge the earth: with righteousness shall He judge the world, and the people with equity (Psalm 98:4-9).
The wilderness and the solitary place shall be glad for them; and the desert shall rejoice, and blossom as the rose. It shall blossom abundantly, and rejoice even with joy and singing: the glory of Lebanon shall be given unto it, the excellency of Carmel and Sharon, they shall see the glory of the LORD, and the excellency of our God (Isaiah 35:1-2).
Sing, O heavens; and be joyful, O earth; and break forth into singing, O mountains: for the LORD hath comforted His people, and will have mercy upon His afflicted (Isaiah 49:13).
For ye shall go out with joy, and be led forth with peace: the mountains and the hills shall break forth before you into singing, and all the trees of the field shall clap their hands (Isaiah 55:12).