Earnest expectation was part of the life of God's people in the Old Testament. The faithful ones were looking for the promised consolation and that promise was finally fulfilled in the incarnation of the Savior. Even though the Savior has come and has won the victory, the waiting of the people of God continues today. They looked for His coming and we also look for His coming.
In Romans 8:13-23, the Apostle Paul places the expectation of Christians today within the context of "suffering". He does this, not to discourage us, but to encourage us. He admits that the Christian life is lived waiting for the fulfillment of the promise and in a fallen world. But even though these things are true, the current state of suffering is as nothing compared to the glory that awaits us, and will be revealed in us and in the material creation. Yes, even the material creation waits for the fulfillment of the promise with an earnest expectation, or literally, with an outstretched head. But why does the material creation also wait?
The apostle tells us that the material creation was made subject to "vanity" because of the Fall of Adam and his children. That is, the material creation is also affected by sin and corruption. So, the material creation waits for that day when its bondage will also be broken and it will be delivered. When we observe the material creation, we find in it a testimony to the corruption of humankind. It is twisted and perverse because it was cursed for the sake of Adam. (Genesis 3:17-19)
So the material creation groans and we (Christians) groan waiting for the redemption. The redemption accomplished by the Savior in His life, death and resurrection is a complete redemption. But, until the Last Day, we witness while we wait; we serve while we suffer; and we hope in the promised consolation. We walk in the footsteps of our father Abraham. "By faith Abraham, when he was called to go out into a place which he should after receive for an inheritance, obeyed; and he went out, not knowing whither he went. By faith he sojourned in the land of promise, as in a strange country, dwelling in tabernacles with Isaac and Jacob, the heirs with him of the same promise: for he looked for a city which hath foundations, whose builder and maker is God." (Hebrews 11:8 ‚Äď 10)