Consider the false idea that the atonement makes it so that we receive rewards above and beyond our actual righteousness. It tells us to put down our labors. It says to stop pulling on the yoke. It teaches that once we are good enough that Christ's mercy will at least bring us into heaven, there is no longer any point to our efforts.
But here, read the scriptures on the matter.
First off, regarding receiving spiritual blessings above and beyond our actual righteousness.
D&C 130:20 There is a law, irrevocably decreed in heaven before the foundations of this world, upon which all blessings are predicated—
21 And when we obtain any blessing from God, it is by obedience to that law upon which it is predicated.
That is perfectly plain. It was given as revelation long after the atonement was performed. It is a truth that is not altered one iota by the atonement.
Now, if you thought that is what the atonement was all about, and these days many people wrongly do, you may think that I just said there is no atonement. Not at all. I just quoted a scripture and said it was true. And now I will quote another one, which is equally true.
Mosiah 3:18 For behold he judgeth, and his judgment is just; and the infant perisheth not that dieth in his infancy; but men drink damnation to their own souls except they humble themselves and become as little children, and believe that salvation was, and is, and is to come, in and through the atoning blood of Christ, the Lord Omnipotent.
19 For the natural man is an enemy to God, and has been from the fall of Adam, and will be, forever and ever, unless he yields to the enticings of the Holy Spirit, and putteth off the natural man and becometh a saint through the atonement of Christ the Lord, and becometh as a child, submissive, meek, humble, patient, full of love, willing to submit to all things which the Lord seeth fit to inflict upon him, even as a child doth submit to his father.
20 And moreover, I say unto you, that the time shall come when the knowledge of a Savior shall spread throughout every nation, kindred, tongue, and people.
21 And behold, when that time cometh, none shall be found blameless before God, except it be little children, only through repentance and faith on the name of the Lord God Omnipotent.
So we cannot be found blameless before God, only through repentance and faith on the name of the Lord God Omnipotent. Salvation can come in and through the atoning blood of Christ.
How are these two different scriptures both true? The answer is laid out plain as day in the verses I just quoted. It says that the reason no man can be saved except through repentance and faith on the name of the Lord is that the natural man is an enemy to God, and has been from the fall of Adam, and will be forever and ever, UNLESS.
And what is that "unless"?
The scripture is perfectly plain. Mankind is an enemy to God and will be forever and ever unless he yields to the enticings of the Holy Spirit, unless he putteth off the natural man, unless he becometh a saint through the atonement of Christ, unless he beomes as a child, unless he becomes submissive, unless he becomes meek, unless he becomes patient, unless he becomes full of love, unless he becomes willing to submit to all things which the Lord sees fit to inflict upon him.
Unless we BECOME something different than the natural man through the atonement, then the atonement is of no use to us, because we are left as if no atonement had been made.
The atonement is the vehicle that makes change possible.
The atonement is NOT a substitute for change. It never has been. It never will be.
And that is the doctrine of the scriptures.