Dostoyevsky on personal sacrifice

I found this passage from The Brothers Karamazov particularly relevant to my life right now. In it, the narrator discusses Alyosha's decision to join a monastery (emphasis added):

He entered upon this path only because, at that time, it alone struck his imagination and presented itself to him as offering an ideal means of escape for his soul from darkness to light. Add to that that he was to some extent a youth of our last epoch--that is, honest in nature, desiring the truth, seeking for it and believing in it, and seeking to serve it at once with all the strength of his soul, seeking for immediate action, and ready to sacrifice everything, life itself, for it. Though these young men unhappily fail to understand that the sacrifice of life is, in many cases, the easiest of all sacrifices, and that to sacrifice, for instance, five or six years of their seething youth to hard and tedious study, if only to multiply tenfold their powers of serving the truth and the cause they have set before them as their goal--such a sacrifice is utterly beyond the strength of many of them. The path Alyosha chose was a path going in the opposite direction, but he chose it with the same thirst for swift achievement. As soon as he reflected seriously he was convinced of the existence of God and immortality, and at once he instinctively said to himself: "I want to live for immortality, and I will accept no compromise." In the same way, if he had decided that God and immortality did not exist, he would at once have become an atheist and a socialist.

There are many times in the middle of that long process of giving yourself to study or training when you wonder if it's worth it. Shouldn't I be doing something that makes a difference? Shouldn't I be stopping injustice right now? Do I really have the luxury to spend this time considering what's true and false, right and wrong, rather than simply acting on my beliefs?

Speaking from personal experience, I think all of us who are in the middle of something like graduate work tend to have those moments, at least from time to time, of feeling tired, worthless, and even embarrassed. Why exactly did I choose to do this rather than pursue something more lucrative with my abilities? Or better, why didn't I start some project that directly addresses poverty and injustice? As a Christian, it's easy to start thinking, am I really honoring God? Shouldn't I be spreading the good news, or something?

Such thoughts surely have a ring of truth, but it's comforting to hear this wise narrator offer the counterargument, that in fact these questions are largely motivated by selfish instincts. Not that this justifies my graduate studies, or whatever. It just reminds me of my natural limitations, that even my good desires--for truth and goodness and justice--can be misleading. I think that's why freedom is so important for Christians. It turns out the most righteous of us can actually be the most wrong, even when they appear to be the most right.