Answer: Healthy growth of the ego takes place when I ascend above it and perform spiritual actions. By doing so, I force the ego to grow to my level.
Suppose I perform a certain spiritual action. As soon as I ascend to its level, my ego also ascends to its level. I yearn to advance, perform the next spiritual action, and ascend to the next level, and my ego ascends further from that level too. This means that to the extent that I grow in spirituality, my ego also grows.
This is how they follow each other, as it says: “He who is greater than his friend, his desire is greater.” It turns out that when you grow to be a good Kabbalist, you become a great egoist.
But then the ego is controlled by the spiritual attribute that you have acquired, which means that you work with the intention in order to bestow, and you push your spirit, your spiritual state, which in its turn pushes your ego upward.
Thus, our spiritual level actually grows thanks to the ego, because everything that the Creator has created is basically the ego, and everything else is its derivatives.
From KabTV’s “Fundamentals of Kabbalah” 11/11/18