Gospel means "good news". In the case of man, the good news is that we have a Saviour from our sin, and that means our sin cannot ultimately separate us from God in judgement. We are assured eternal life, not by anything we do, but by everything He did. Praise God the Father and Christ for such love and mercy!
Jesus came into this world for the purpose of redemption-our redemption, and this to the praise of His glory alone. He died at the hands of men, predestined to take our punishment so that he could be declared Lord of all.
It's hard to fathom God becoming flesh and taking our sin-declaring us righteous who knew no righteousness, but that is the good news!
You can do nothing to earn salvation-nothing-nada...and why would any one want to, when someone else has already earned it for us.
John 3:16 rings true today and will eternally ring true for all of God's children. Yes, it's that simple. Don't trust your self, trust in God's Word.
For by grace we are saved through faith, and that not of ourselves, ...not of works, lest anyone should boast...