One of the teachings that I do with leaders when I am in India and Haiti has to do with the pattern of Jesus' life and ministry that we see in Matthew 4. It is not explicit, but you can see the pattern of Devotion-Intercession-Proclamation-Demonstration throughout the chapter:
Matthew 4 Pattern of Jesus:
Devotion (Word - Temptation in the desert 4:1-11)
Intercession (Fasting 4:1; Withdrawal 4:12)
When we live by this pattern, we see gospel fruit in our lives and our ministry. As Evangelicals, we have focused quite heavily on personal and corporate devotion to The Lord, on prayer/intercession, and on proclaiming the gospel. But, we often leave off the last part, which is demonstrating the gospel. Jesus went around preaching the gospel of the Kingdom and also healing, casting out demons, performing miracles, and setting things right. He told people what the Kingdom was and announced its coming and he then showed them what life in the Kingdom of God looks like. We miss this point rather spectacularly, I think.
We have separated the preaching of the gospel from the living out of the implications of the gospel in a broken world. But, if we see the work of Jesus (see Matthew 9:35-38 and 10:5-15 for further examples) as providing a picture of what life in His Kingdom looks like, then the good works that we do make a great deal of sense. We are not doing good works to work our way into Heaven. We are doing the good works because Heaven has worked its way into us and we are witnesses of what life looks like when it is lived with Jesus making all things new. Our works become our witness.
Look at what Jesus said to the followers of John the Baptist when they came to him and asked if He was the one that they were expecting of if they should expect another?
Now when John heard in prison about the deeds of the Christ, he sent word by his disciples and said to him, "Are you the one who is to come, or shall we look for another?" And Jesus answered them, "Go and tell John what you hear and see: the blind receive their sight and the lame walk, lepers are cleansed and the deaf hear, and the dead are raised up, and the poor have good news preached to them. And blessed is the one who is not offended by me." (Matthew 11:2-6 ESV)
Jesus' works witnessed to who He was. They also declared the appearance of the Messiah and the inbreaking Kingdom of God that the Jews had been waiting expectantly for. They were not just an add-on that proved that He was the Son of God. They demonstrated what life lived under the reign of God would look like.
In the same way, I believe that the Church is called to both proclaim and demonstrate the gospel. We too, as the Body of Christ, are to preach of Jesus and show the world what life looks like when it is lived under the reign and rule of God together. This is a battle as the world seeks to drag us back towards its way of seeing and doing things. But, when we pray, study Scripture, and do what it says, we find that we are living a different kind of life - a Heavenly life - and we are inviting others to live it with us.
Demonstrating the Gospel is not a theology of good works so that we will be justified before God. It is the way that we experience God in a fuller way and how we tell His story and help make things right here on earth - "thy will be done on earth as it is in Heaven."