The gospel is good news: that is what the word 'gospel' means - "Good News!"  However, everything that Jesus said and did is unknown unless somebody brings the Good News.  Although the life and death of our Saviour was physically located in the Holy Land, the benefit of His sacrificial ministry will come to everybody ... but first they need to hear and believe the Good News (Romans 10:14-15).  The task of the Apostles was to start proclaiming the gospel, in as many places as possible (Romans 15:20) until the gospel has become universally known.  Through their inspired writing, their gospel ministry continues in many languages up to the present time.  Everybody who helps to explain the gospel, serves the Lord.
 
To become a 'servant of the gospel' is much more than a philosophical idea.  God personally commissioned Paul (Acts 26:16-18) for the task; and he chose to submit to be a servant of Jesus Christ and His gospel (Romans 1:1).  Wherever courageous believers proclaim Christ, the church grows and the Lord is glorified (Colossians 1:3-7).  They may attract ridicule, and persecution, but they do it, persevering in sharing the gospel, because they are being obedient to the Lord of the gospel (Matthew 28:18-20).
 
The dynamic of gospel ministry is simple. Every believer is called to explain their faith (1 Peter 3:15), so that those who understand and obey the gospel call will be saved.  So, wherever the Christian goes, he or she is a mobile gospel container.  That was how the gospel first spread: as Christians were persecuted they took the good news of Jesus with them, and the church grew (Acts 8:1-4).

The gospel is not a secret to be kept locked up in the container; it is intended to be released everywhere because it is globally applicable.  So, it is our privilege and responsibility to release the gospel into the office, hospital, factory, transport hub, construction site, publishing house, lawyers' chambers, social club, sports venue, music festival and holiday resort.  If every believer did that the Word would soon spread - and the salvation purpose of our Saviour, who died for the sins of the world, would be well served.