The immune system, which differentiates self from non-self, grows through its response to challenges. We are not born with a fully, functioning immune system. Perhaps life’s challenges do the same thing for us. Through them, we become better able to define who “we” are.
As the immune system grows (faith?), and matures, it attacks the non-self, the lies and the hypocrisies we have believed and we find the truth of our “self’s” that were ever-present and perfect, from the moment His perfect artistry created us.