In my view, the Jukai ceremony celebrates and commemorates two facets that must exist quite on their own, apart from the ceremony … the ceremony itself works no magic, and merely marks their necessary arising:
First, there is the vow and aspiration to live in accord with the Precepts. All the Precepts come down to our seeking, as we can, to live in a manner harmless to ourself and to others, and healthful and helpful to ourself and others, knowing that ultimately there is no separation between ourself and others. If we are living already in such manner … seeking as we can do be a good father/mother/son/daughter/friend/human being … then (in my view) we have already “undertaken the Precepts”, and the ceremony merely commemorates that fact. However, the ceremony also signifies our vow to continue to do so in the future.
Second, the Jukai ceremony stands for our commitment to continue Zen Practice, our commitment to the wider Buddhist Sangha (and, on some level, to a specific Sangha such as Treeleaf), and our linking ourself symbolically to all the Buddhas and Ancestors, and all the other many people, who have walked the Way before us in the past. Again, if one already feels this in one’s heart, then the ceremony merely celebrates that fact, I believe.
Thus, the ceremony itself will not “make you into a Buddhist”. If one does not feel that one “is a Buddhist” already, then the ceremony will do nothing but kill some time in your life. On the other hand, if one has developed a feeling within that one has trust in our Way, in the Buddhas and Ancestors and their Teachings, and will continue to seek to make those the foundation of one’s own life … then one is already a “Buddhist” whether one has the ceremony and receives a robe, fancy name or not.
So, if that is the case, why bother with the ceremony at all?
Again, this is for each person to determine in their own heart. However, personally, I do feel that it is important at certain times to make a formal and open statement of vow and commitment, both for one’s own sake and for the benefit of others in the Sangha and general society who might be encouraged by watching you do so. It is not quite like saying that one is “getting married” versus “just living together” with Buddhism (for one, there is no alimony involved with Jukai if you change your mind later. :? ) But it does signify that one is making a public affirmation of one’s commitment.