I am in a Church that teaches “The Grace ” message. That is that Christ died for the sins of the whole world, once and for all. There is no need to ask for forgiveness of sins, as all sins have been forgiven. All that’s needed is to believe in the Lord Jesus. As Jesus Himself said:” Believe in The One He has sent, and you will be saved.”
If by “believing in the one He has sent” you mean entrusting your eternal destiny to the Lord’s completed work on the cross rather than just expressing an intellectual understanding that Jesus is the Savior of mankind, I’m OK with that as far as salvation goes. Salvation is based on belief alone.
But as Paul explained in 1 Cor. 9:24-27 and other places, salvation is only the first step in a believer’s relationship with the Lord. Living a victorious life as a believer comes next and for that some effort on our part is necessary. This effort includes putting off our old selves and being made new in the attitudes of our mind (Ephesians 4:22-24), refusing to conform to the pattern of this world and yielding ourselves to the Lord’s will for us (Romans 12:1-2), and remaining in fellowship with the Lord by confessing when we sin to keep us pure from all unrighteousness (1 John 1:9). These things don’t affect our eternal destiny, which is a free gift, but they do determine the quality of our life as a believer in the here and now. Much of the New Testament is devoted to helping us accomplish this.