Beginning on page 20 of his book The Discipline of Grace, Jerry Bridges wrote the following few paragraphs. I have abbreviated some, though the gist remains the same.
What one word describes the message you most needed to hear as an unbeliever? I suggest that the word is gospel. It is the gospel that is the power of God for salvation. We need to hear that Jesus died for sinners and that if we come to him in faith, we will receive the forgiveness of our sins and the gift of eternal life.
What one word describes the message we most need to hear as believers? I get a lot of different answers to that question, but most of them can be summed up with one word, discipleship.
But there is something more basic than discipleship, something that actually provides the necessary atmosphere in which discipleship can be practiced. The one word that describes what we must continue to hear is gospel.
We need to continue to hear the gospel every day of our Christian lives. Only a continuous reminder of the gospel of God's grace through Christ will keep us from falling into good day--bad day thinking, wherein we think our daily relationship with God is based on how good we've been.
It is only the joy of hearing the gospel and being reminded that our sins are forgiven in Christ that will keep the demands of discipleship from becoming drudgery. It is only gratitude and love to God that comes from knowing that He no longer counts our sins against us that provides the proper motive for responding to the claims of discipleship.