"Yes, salvation is free BUT it will cost you everything."
"Sure it's by faith in Christ BUT you also have to get baptized."
"Of course it's a matter of believing in Jesus BUT you also need to go to church, read your Bible, blah, blah, blah."
These statements (and tons more) litter far too many Gospel presentations of far too many preachers today. They give the Gospel a big BUT and that is not flattering to the message of God's grace.
The Apostle Paul put it this way in Romans 3:22-24,
"This righteousness is given through faith in Jesus Christ to all who believe. There is no difference between Jew and Gentile, for all have sinned and fall short of the glory of God, and all are justified freely by his grace through the redemption that came by Christ Jesus."
In other words we are saved by faith alone through Christ alone and by nothing on our own. Jesus did all the work. He died so we can live. He rose so we will rise from the dead some day.
The only thing we must "do" is believe. When Jesus was asked by the Jews in John 6:28-29 what works they must do to be saved his answer was clear, "The work of God is this: to believe in the one he has sent.”
We put our faith in Jesus and God forgives us for all of our sins (past, present and future), adopts us into his family and indwells us with his Holy Spirit to begin that work of transformation in our lives. Some people say that this Gospel is too good to be true but I say it's too good AND it's true!
But, as my friend pointed out to me, if there's one BUT in the Gospel it's found in Ephesians 2:3-5,
"All of us also lived among them at one time, gratifying the cravings of our flesh and following its desires and thoughts. Like the rest, we were by nature deserving of wrath. BUT because of his great love for us, God, who is rich in mercy, made us alive with Christ even when we were dead in transgressions—it is by grace you have been saved."
So don't add to the Gospel. Don't add caveats or small print to the free gift of God's grace. We are saved by simple faith in our amazing Savior! And it's this good news message that inspires me to serve him with all of my heart, not because I have to in order to be saved, but out of sheer gratefulness for God's no-strings-attached gift of eternal life.
No if's, and's or but's about it.