But I make known to you, brethren, that the gospel which was preached by me is not according to man. For I neither received it from man, nor was I taught it, but it came through the revelation of Jesus Christ.
Galatians 1:11-12 (NKJV)
The Apostle Paul told the Galatians that the gospel is not based on human traditions, but rather God's revelation to all peoples. As a result, you cannot add to or subtract from the gospel—all you can do is remain faithful to the good news of God's salvation through Jesus Christ.
When we add something to the gospel, we are expecting works and rejecting grace as the foundation for God's acceptance of us. When we take something away from the gospel, we are depriving it of its power to save sinners and sanctify saints.
Sometimes believers believe there are multiple versions of the gospel. They can also choose and adhere to their preferred version. While we have four gospel accounts that focus on Jesus' historicity, there is only one gospel message in which salvation is found in Christ alone. (Acts 4:12) No one can claim to have received salvation through a "better" gospel than the rest of us. And, most likely, this "better" gospel is a distortion of the true gospel.
By hearing and believing the gospel in all its fullness, you will become increasingly aware of God's incredible presence and power in your life. You will experience an increasing sense of grace and peace because of your intimate knowledge and personal relationship with God the Father and Jesus Christ the Lord. (2. Peter 1:2)
Do not see the gospel as something you must have to be saved, or as a lesson for new and young believers. You need the gospel more than you realise. The gospel is essential in all aspects of your life.
What is God saying to me here and what must I do?