For all who are led by the Spirit of God are sons of God. For you did not receive the spirit of slavery to fall back into fear, but you have received the Spirit of adoption as sons, by whom we cry, "Abba! Father!" The Spirit himself bears witness with our spirit that we are children of God, and if children, then heirs—heirs of God and fellow heirs with Christ, provided we suffer with him in order that we may also be glorified with him.--Romans 8:14-17 (ESV)
Isn't the Lord so merciful? We deserve Hell; He gives us the glory of Heaven. We deserve condemnation; He takes the punishment for our sin upon Himself. We are unholy rebels and criminals--yet somehow, God adopts us. He is pleased to call filthy sinners His children. All glory to God!
Because of God's gracious adoption, we can call the almighty Lord of the universe "Daddy." We weak and unrighteous humans can lean on His bosom, find solace in His love, know He hears our prayers, and receive a glorious inheritance in Heaven.
However, in this world, we will "suffer with Him in order that we may be glorified with Him." We have not yet come into our inheritance. When we are afflicted with trials, we should think of these verses and (1) hope in our future glory, and (2) know that our suffering is necessary if we wish to be glorified in Heaven.