I'm intrigued by Kierkegaard's system for reasons that conflict - it seems there's a tenuous balance of faith and knowledge at play here. I'm always curious to hear reasons for aligning with Christianity, especially when the Christian in question is highly esteemed in the intellectual world. My interest in this text specifically stems from the mix of approaches to understanding the world, the divine, and how the two inform one another; historically prominent religious themes, like blind "faith" and denial of the possibility of any understanding, come together in such a complex way here.
It's fascinating that Kierkegaard validates a sort of ignorance by way of illumination. The goal of Fear and Trembling is to remind Christians that their faith is not that of Abraham's, but individuated faith, and, in most cases, faith that's mediated by the universal, ethical realm. Most are not connected directly to God, and may not ever be. And if such a connection does occur, the individual won't have knowledge of it or the responsibility of acting under it until "called upon," or something comparably passive on the part of the individual. And, in fact, we can't recognize others who have been called upon and therefore joined the religious realm, because they can't tell us about it. That concept swallowed and flagged with regular reminders, so as not to stray back to correlations that shouldn't be made, how should one proceed about one's daily activities? Or one's faith, for that matter?
Kierkegaard says: don't worry! In terms of duty, those who've been pulled into absolute relation with the absolute have much more pressing moral concerns than those still occupying the ethical realm. For AMUs (Aesthetes Mediated by the Universal), duty is to other individuals, through the ethical. In other words, be morally commendable, and be ready in case of an opportunity to join the religious realm. And in the case of dealing with those who may have acted outside the ethical realm (like Abraham), we should proceed as we would with other rule-breakers. So we AMUs are really practicing a form of intentional ignorance by way of acknowledgement of incomprehensibility - but all this post-Kierkegaardian illumination.
The moral: Ignorance is okay, if you know you're doing it.