The gospel is simple, and when we believe on Jesus, we are saved. And our salvation rests in the hands of Jesus. Nothing can separate us from Him, not even ourselves. It's about faith. So if you've believed, don't let anybody steal your faith from you because you don't meet with their approval in some way.
It's possible to be tossed to and fro in this life, but God is perfectly capable of finishing what He started in you. Just trust Him. Don't worry and don't be afraid.
Be at peace, and be content with Christ, and every good thing that God does for you and gives you, no matter how big or small, it's all a gift. God is no respecter of persons, and He has each one of us who has believed. Don't think yourself more important if you've been given more faith or more understanding, or less important if you're struggling. Grace abounds for all of us, and for those struggling, even more, exactly what is needed.
We preach 1st Corinithians 15:1-4 as the gospel, how Jesus died for our sins, was buried, and rose again on the third day. According to the scriptures. Make sure you get every word exactly right with the perfect understanding of all it's implications or you didn't really believe, some will say.
Yes, all your sins are forgiven, past, present, and future. And you should believe it, because it's the truth. But I do believe it's possible to be saved without having a deep understanding of the gospel and all it's implications. Do you suppose the thief on the cross was able to quote a yet-to-be written 1st Corinthians 15:1-4 and explain to some random person how it's the blood of Jesus that's made him worthy and how his past, present, and future sins are all forgiven?
At it's core, the gospel is a simple belief in Jesus, an understanding of who He is and what He did, and that He will save you, if you'll believe. And when you believe, Jesus himself saves you. It's not the persistence of the belief that keeps you saved, it is Jesus.
Some will use scripture in 1st John, which is written to give believers assurance of their salvation, and try to reverse it, into a logical fallacy and try to use it to accuse people they're not saved if they don't have an adequate witness of the gospel at any given time. Adequate according to their own standard, not God's. Yes, the Holy Spirit witnesses and works in a believer, perhaps not to some random man's satisfaction, but it does not matter what anybody else thinks. And however anybody wants to twist scripture, the gospel still stands true.
I've found in my life that God is faithful to us, even when we're not particularly faithful to Him. Some people get really offended by this. I'm not saying we shouldn't be faithful. That's not it. But rather take comfort, because if we've believed on His Son, He is faithful to us, no matter what.
Everywhere today offense is abounding. This is something out of the ordinary. I think we're in uncharted territory. And my response lately has been to pull back and pray and have faith and trust the Holy Spirit will guide me into all truth and righteousness, to keep me on the right path.
I rest in the sure knowledge of my salvation, that it is finished. I take assurance and comfort knowing that my salvation rests in the hands of Jesus, and there's nobody and nothing that can separate me. And I choose to walk in the faith that I'm covered by the blood of Jesus, and I stand before God in Christ alone. Justified and made worthy by His righteousness imputed to me by faith. It's my prayer and my belief that Jesus, and His gospel, the forgiveness of our sins, and the grace imparted to us, be made manifest in us all, who have believed. And I believe it will be done, one way or the other, it is the work of Christ. And He won't leave a single one behind.