D&C 88

The Savior continues to teach new doctrine not necessarily taught in other scripture -

"...unto every kingdom is given a law; and unto every law there are certain bounds also and conditions.
39 All beings who abide not in those conditions are not justified."  (Doctrine and Covenants | Section 88:38 - 39)

In other words, not justified is being not in accordance, reconciled or in alignment with that kingdom.

Of those that strive to be justified in accordance with the conditions and laws of the Celestial kingdom -

"...the day shall come when you shall comprehend even God, being quickened in him and by him."  (Doctrine and Covenants | Section 88:49)

I specifically note that quickened in him and by him is the power of Christ or the power of the atonement.