It was understood from the beginning that in mortality we would fall short of being perfect. It was not expected that we would live without transgressing one law or another.”
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A Mediator, a Redeemer, was chosen, one who would live His life perfectly, commit no sin, and offer “himself a sacrifice for sin, to answer the ends of the law, unto all those who have a broken heart and a contrite spirit; and unto none else can the ends of the law be answered.”4
-President Boyd K. Packer, “The Atonement,” October 2012 General Conference