The word “Gospel” is the English translation of the Greek word “eu-angelion”. “Eu-angelion” means “good news”. The New Testament book of Mark opens with the words “The beginning of the good news about Jesus the Messiah”. It is that kind of good news that Lutherans are talking about when they talk about this word “Gospel”. This is why we call the books of the Bible that are biographically about Jesus “Gospels”.
The word Gospel is very closely related to the idea of Grace. Lutherans see grace as being God’s simple favor shown to humans who could not deserve that favor. Simply speaking, God likes — even loves — you for no good reason. He loves you because He does, and He sent His Son to die on the cross and pay for your sins because He loves you. He doesn’t love you because He is obligated in any way to love you.
Unfortunately, human beings have a tendency to try to make ourselves loveable to God. We want to make God obliged to love us because we’re good people or because we do good things. God doesn’t want to be forced to love us, He just wants to love us. However, our human nature makes us strive to build up credit with God so that we can lay some claim to His love. We want to be able to say “God loves me because I . . . “. This is called “self-justification”. Religions throughout the world operate on this level of seeking God’s favor through our actions and/or attitudes.
This was the problem that Lutherans encountered early in the 1500’s. People were trying to find all sorts of ways to make themselves worthy of God’s love – through extra church services or through becoming monks or through giving money to the church. None of those things were necessarily bad, but they were done for the wrong reasons. God doesn’t want us to do good things because we’re trying to make ourselves worthy, He wants us to do good things because they’re good. The Gospel frees us up to do good things because they’re good, not because we’re trying to impress God. That’s pretty good news.