There is no way, given our limited perspective in this life, that we can measure the eternal impact of pure testimony. Perhaps only when we are able to look back on the whole of our existence, able to see things as they really are, . . . and measure just how much difference has been made by human testimony.
"Obedience [is not] a mindless shifting of our personal responsibility. . . It is tying ourselves to a living God who will introduce us—as soon as we are ready—to new and heavier responsibilities involving situations of high adventure."
Elder Neal A. Maxwell
Exposure to truth alone is not enough. The real issue of our conversion centers in our courage to follow Christ, stand up for, and be numbered in His cause.