On the face of it, the transition a couple makes when they marry is to go from two persons who love each other spontaneously, to two persons for whom sharing a life of love becomes something that they are committed to. But what can this commitment amount to? Everyone has heard the news that the human heart cannot be commanded. You can't fall in love on purpose, and you can't remain in love just because you think that you have good reasons to do so. More than that: it is the nature of erotic love to be the deep origin of what is meaningful in a romantic relationship. The very notion that one could someday love someone out of a sense that this is what one promised seems to empty everything out of erotic love and make it unrecognizable. In his works Either/Or and Stages on Life’s Way, Søren Kierkegaard’s pseudonym Judge William defends the idea of a vow to love. Specifically Judge William’s writings on marriage constitute an attempt at a phenomenology of the possibility of “choosing” one’s own love for someone, and a more mature form of erotic love, one in which the erotic love is refocused on the resolution itself, flowing from this choice. This dissertation is an attempt to reconstruct William’s account. In particular, the dissertation focuses on William’s counterintuitive views on decision. William thinks that pre-marital erotic love is transformed by the decision to become (and remain) married; but, importantly, this is not a decision that bears authority in a normal way. Normally, if a decision has authority, the authority comes from the reasons one has to make the decision; and those reasons must, of course, have validity to one independently of one’s own act of choosing. Instead, in what William calls choosing oneself, the volition that one invests in the action is how one takes possession of the ground one has for the decision. This becoming, thinks William, is what one is accomplishing when, at a wedding, one commits to continue to love someone. The decision itself is (in part) what makes the love exist in the crisis of the ceremony and the marriage.