“Be Perfect Even as I or Your Father Who Is in Heaven Is Perfect”
We are perfect when we are whole, fully formed, finished. The word finished is most important here. We cannot through discipline and self-will be perfect in the sense that we are finished. We cannot conquer the flesh, overcome the trials and tribulations and sins of this world, on our own. We become finished only in and through Christ. Moroni explained that the Saints of God are
“continually watchful unto prayer, relying alone upon the merits of Christ, who was the author and the finisher of their faith” (Moroni 6:4, italics added).
In short, we become perfect, fully formed, finished, in Christ (Moroni 10:32). His grace is a divinely given enabling power a sacred source of strength which enables us to accomplish what we could never accomplish, worlds without end, on our own.
We become perfect in Christ to the degree that we trust perfectly in his infinite ability to make of us, now unworthy creatures, persons capable of and comfortable with celestial society. In speaking of that celestial glory, the revelation attests:
“These are they who are just men made perfect through Jesus the mediator of the new covenant, who wrought out this perfect atonement through the shedding of his own blood” (D&C 76:69, italics added)