If I had one sermon to preach it would have to be about the character of God. God is love and from the start this is God’s motive for dealing with the sin problem. If I had only one sermon to preach it must include God’s forgiveness for sin, His justification and sanctification of sinners. The sermon would need an understanding of God’s transforming power by the Holy Spirit working in the life. All of this and more becomes the center of focus when the redeemed are standing by the Sea of Glass (Revelation 15:2,3). Here is celebration, worship, and the joy of knowing that sin and suffering is gone forever. If I had one sermon to preach it would focus on the fact that we are the victors.