"And in me too the wave rises. It swells; it arches its back...." — Virginia Woolf quote meaning

And in me too the wave rises. It swells; it arches its back. I am aware once more of a new desire, something rising beneath me like the proud horse whose rider first spurs and then pulls him back. What enemy do we now perceive advancing against us, you whom I ride now, as we stand pawing this stretch of pavement? It is death. Death is the enemy. It is death against whom I ride with my spear couched and my hair flying back like a young man's, like Percival's, when he galloped in India. I strike spurs into my horse. Against you I will fling myself, unvanquished and unyielding, O Death!