The Gospel is well encapsulated in the words of Jesus who said, "I Am the Way, and the Truth, and the Life."
In verse 11 Jesus said, "Believe me that I am in the Father, and the Father in me" meaning quite literally that Jesus is Yahweh in the flesh.
The Jews quite rightly look to God for salvation, which they did by following the commandments, for the most part sincerely and faithfully, but never perfectly due to our human nature, to which end God, the perfect one made a way of escape, so that ALL who believe in Him shall be saved.
That Jesus is Yahweh God is clearly stated in scripture. Read on: -
So now, instead of following Old Testament law, people can simply believe in the Lord Jesus Christ and follow Him all the days of their life.
How and what would we follow as children and servants of God?
They claim to know God, but by their actions they deny him. They are detestable, disobedient and unfit for doing anything good. Titus 1:16
We know that we have come to know him if we obey his commands. The man who says, “I know him,” but does not do what he commands is a liar, and the truth is not in him. But if anyone obeys his word, God’s love is truly made complete in him. This is how we know we are in him: Whoever claims to live in him must walk as Jesus did. 1 John 2:3-6
...We know that we all possess knowledge. Knowledge puffs up, but love builds up. The man who thinks he knows something does not yet know as he ought to know. But the man who loves God is known by God. 1 Corinthians 8:1-3
If I have the gift of prophecy and
can fathom all mysteries and all knowledge, and if I have a faith that can move mountains, but have not love, I am nothing. 1 Corinthians 13:2
The problem with OSAS is, the word ALONE attached to faith intends to separate faith from works (of love) which causes division among Christians.
For we also have had the gospel preached to us, just as they did; but the message they heard was of no value to them, because
those who heard did not combine it with faith. It still remains that some will enter that rest, and those who formerly had the gospel preached to them did not go in,
because of their disobedience. Let us, therefore, make every effort to enter that rest,
so that no one will fall by following their example of disobedience. Hebrews 4:2,6,11
So it is clear that we should combine faith with works(of love) and LOVE is the fulfilment of the law.
If we don't submit and surrender to the Lawgiver and the Judge then we'll become lawless and follow our own will and gratify the desires of the sinful nature.
If we have faith ALONE that can even move mountains but don't have Love, our faith is dead and we are nothing but a worthless servant not known by God and thrown out into the darkness where there will be weeping and gnashing of teeth.
For in Christ Jesus...the only thing that counts is faith expressing itself through love. Galatians 5:6
I asked you about your simple and honest view of the Gospel because I noticed you said that you remember the death and resurrection of Christ without mentioning His life.(that He lived while on this earth, walking in Love which is in obedience to the commands of the Father) Many OSAS no longer include that part in the gospel for whatever reason, I'm not sure, but it must be because Jesus walked in obedience to God's commands, so if we must walk as Jesus did(1 John 2:3-6) to truly know Him and be known by Him and not be rejected(Matthew 7:11-12, 21-23)but included in Him,(Ephesians 1:13) in His body whom He will save when He returns(Ephesians 5:23) then it will destroy OSAS doctrine of a faith ALONE that saves.
Now, brothers, I want to remind you of the gospel I preached to you, which you received and on which you have taken your stand.
By this gospel you are saved, if you hold firmly to the word I preached to you. Otherwise, you have believed in vain. For what I received I passed on to you as of first importance: that Christ died for our sins according to the Scriptures, that he was buried, that he was raised on the third day according to the Scriptures...1 Corinthians 15:1-8
Or this above must be the reason. But what did Paul say and declare?
I will not venture to speak of anything except what Christ has accomplished through me in leading the Gentiles to obey God by what I have said and done— Romans 15:18