Verse 17 says, "If so be that we suffer with Him, that we may be also glorified together." Three ideas are conveyed here. (1) Christ and His people are one; therefore, when He suffered and died, we were in Him and we partook of the efficacy and blessings of His sacrifice. (2) Because of chis oneness with Him, there will be sufferings for us to bear, for His sake and the gospel's. (3) Being still frail flesh and subject to all of the infirmities, afflictions, and diseases of the body, and eventually death, we shall have to suffer trials on this earth.
(Vs. 18) No trial or suffering is easy. If trials were without pain and discomfort, they would not accomplish the purpose for which they are sent (James 1:2-4). But when we look at all of earth's sorrows, sufferings, and trials in the light of His eternal glory, when we shall be like Him, enjoy His presence, and partake in His perfect kingdom, we look on these present inconveniences as NOTHING. They are not worthy to be compared to that glory (I John 3:1-3).
(Vs. 19-22) The word "creature" in these verses is best read "creation," as in Verse 22. There will be a new earth, but the revelation of that new earth awaits the resurrection of God's people. The earth on which we live has become subject to decay, disease, and death because of Adam's sin. This state shall not continue, for the creation shall be delivered from this bondage as we shall be delivered from our corrupt bodies (II Peter 3:13). The earth, materially, is the same as before the fall; after the restoration it will be perfect. (Read these verses from the Amplified version.)
(Vs. 23) Not only does the whole creation groan and travail under the weight of sin, but we also are burdened with the old nature and long for the joys of full redemption (Rom. 7:24-25; I Cor. 15:42-49).
"The first-fruits of the Spirit" means that the believer, under the sanctifying work of the Holy Spirit, already enjoys a taste of what heaven and life eternal shall be. Heaven will be complete fulfillment and perfection of what we enjoy in part (I Cor. 13:12-13).
(Vs. 24) Actually, while we are justified, sanctified, and secure in our Redeemer, we are NOT YET SAVED to the full extent of that blessed word. Full satisfaction is that for which we long, look, and hope (Psalm 17:15). That blessed hope of being like Christ is not simply a wish or a desire, but a desire based on God's promise and the full expectation of its completion in Christ. A desire already experienced or seen is not hope. When we are in full possession of heaven, hope becomes reality and faith gives way to sight.
(Vs. 25) But when our hope of forgiveness, salvation, and full redemption is in Christ and His blessed promises (though we do not yet see nor possess the fulfillment of all His promises), we patiently wait for them; for His promises are as sure as His Word (Titus 1:1-2; Heb. 11:13).
(Vs. 26) The word "likewise" seems to say "not only does hope of future glory (in and through His Word) lead us to patiently wait for deliverance and resurrection, but the Holy Spirit also bears us up in our weakness." We don't know what prayer to offer, what things to ask, or what is the will of God; but the Holy Spirit prays in us and for us with groaning too deep to utter. He enables us to pray according to the will of God (John 14:16-18; John 16:13-14).
(Vs. 27) "He that searcheth the heart" is God. No man knows the heart of another, nor does any man fully know his own heart (Luke 16:15). The Lord knows our motives, our thoughts, and our intentions (John 21:17). He knows the mind or the purpose and providence of the Spirit of God, and He makes intercession for the believers according to and in perfect harmony with the will of God for them.