“There is always hope, Severus, even if it is not for ourselves,” Minerva said. “No matter the setbacks or the defeats, there is always hope. We will not surrender to despair, we will not capitulate to Darkness. Even should we die, we will die with hope for tomorrow. Even in our final breath, we will know that our triumph will come. We will die with that hope in our hearts, if we must, but today, we shall live in it. Even should he win the day, that pathetic little toe-rag who fancies himself a lord of wizards, even then, we will know that it will not last. Hope will shine before us always, an eternal star that urges us forward even as we pass through the valley of despair. So proceed with hope, Severus, not only with regret and recriminations, no matter where it leads you, even if it leads you into darkness and death. Hope will be there. Remember it and look to its light even if you breathe your last, and that hope will carry you beyond the darkness. Hope, love, faith: they together shall vanquish the Dark, and it is in us that they live.”
“And when we are dead?” Severus asked, morose and cynical. “Where, then, is that hope? Where, then, love?”
“Do not despair,” Minerva replied gently. “They continue in the human heart, always. And they will triumph over dark deeds, cold indifference, and selfish desires. Love and compassion may sometimes seem very far away, but the good is there in the human heart, and if we must make sacrifices to ensure the good, that is just more proof of it. The proof of it is in you, Severus. In what you do and in what you give, in the choices you now make.”
“You sound like Albus,” Severus said glumly.
“Thank you.” Minerva smiled. “He taught me well.”
~ Death’s Dominion, Chapter 9, “Though they be mad and dead as nails”