Joseph Smith said: We cannot be perfect without the fathers, &c. We must have revelation from them, and we can see that the doctrine of revelation far transcends the doctrine of no revelation; for one truth revealed from heaven is worth all the sectarian notions in existence.
We all know that the fathers cannot be made perfect without the children, nor the children without the fathers, but Joseph Smith offers interesting insight into the meaning of this phrase, for he says "We must have revelation from them". Who? The fathers. We must have revelation from the fathers, our ancestors, in order to be made perfect. Do we believe it?
And how shall we get the fathers to provide us with revelation? Shall it not be by doing work for our ancestors?
Is the Holy Ghost the only spirit that influences and reveals things to the souls of men? No, for our own ancestors must reveal things to us if we are to be made perfect.
And this is no surprise, for does not the entire host of the adversary not also offer its competing whispers, its suggestions, and even, on rare occasion, its manifestations. Surely if evil spirits have power to speak to our minds with temptations then the spirits of our righteous ancestors are no less capable and willing to speak to us as well. And indeed, that is actually plainly taught, for Joseph Smith said "... angels come down, combine together to gather their children, and gather them." It is their children that they gather. They combine together to gather them. They whisper and suggest and inspire their descendants who will hearken no less potently than the adversary and his minions do.