There is a story Jesus tells about planting seed. The seed gets planted in all sorts of conditions; and, as a result, there is a variety of fruitfulness. Jesus later reveals to the disciples that the story is a description of the gospel, and how people respond to it. The word of God is scattered, connecting with the hearts of people. It bears fruit depending on the condition of the heart.
Then, Jesus starts talking about lamps. If a person lights a lamp, it does not do any good to put a bucket over it. A lamp needs to be out in the open, if it is going to do what it is meant to do.
Seed is a very good metaphor for the gospel. Seed gives life, provides nourishment and reproduces.
Light is alos a good metaphor for the gospel. It reveals the way, exposes what is really true, and is not worth anything if it is hidden away.
I would like to draw two conclusions from this. First, Christians are generally concerned with the direction the world is going. They consider the course of the things to be moving in a decidedly negative direction. Yet, the power to revolutionize the world lies hidden in their hearts. People are designed to fellowship with God. And the gospel holds the key to why they cannot, how they can correct this, and how to move into a greater, more intimate relationship with God. The light that leads mankind back to God is hidden under a bucket of their making.
Second, the gospel is a specific message that has ramifications in all areas of life. A large part of the world is blinded by the enemy of all. People need to apply the gospel to what separates man from God, in order to break down that barrier that separates them. But they cannot see the solution in the gospel.
Part of the process of re-uniting man and God is getting man to see past the enemy's deceptions and to discover the solution. there are many devices that can break through the deceptions. Prayer, love, service, kindness, changed biography, even reasonable speech are all means ti pierce the darkness. And there are more.
Both parts of the process need to be employed. One to break the hold of the enemy. The other to apply God's solution to the heart of someone seeking God's love. Often, groups of Christians apply one or the other.