Perhaps the best way to define the symbol is to contrast it with other representative forms that, like the symbol, stand for or point to something beyond themselves.
IMAGES (pictures, statues, photographs)Each of these representative forms may take on a symbolic nature and/or may point to some particular aspect of the symbol, but they do not point to the peculiar nature of the symbol nor are they definitive in every situation. A symbol is a representation which indirectly reminds of or refers to some other reality, serves as a vehicle for the conception of that reality, and actually and effectively participates in that reality. A symbol may be arbitrary in which case it is established by common consent as opposed to having a natural or historic relationship with that which it represents: e.g., a key represents power or possession or a cross represents the Christian faith. A symbol may be evocative, in which case its meaning is suggested by engendering certain attitudes or feelings rather than by any direct statement: e.g., the American flag. Since symbols need not imitate what they represent and since they usually refer to something that is in a different and higher category, they are ideally suited for expressing religious truths.
Images imitate what they represent; whereas symbols need not resemble the thing which they symbolize -- they need only to suggest or associate.
GESTURES (shrugging the shoulders, bowing the head)
Gestures express or embody their meaning as spontaneous, visible extensions of inner attitudes. While many gestures are symbolic, not all symbols are gestures or involve action.
SIGNS (dinner bell, traffic sign, smoke)
Signs announce some fact or give notification. Their role is practical or instrumental, they have an intellectual appeal and call for an immediate response.
Baron Friedrich von Hugel was pointing to this in his statement, "I kiss my daughter in order to love her as well as because I love her." He kisses her because he loves her. Love requires an expression, a way of showing itself, of making itself felt; and a kiss is one way of doing this. But what of the other part of the statement? Kissing can express love, but can it create love? Probably not. But perhaps von Hugel is saying that his love for his daughter will grow as there are more outward expressions of it. The kiss is a symbol of love -- it enables him to communicate this love to his daughter who can in turn respond to it, thereby enriching that love. And at the time that he kisses her, the kiss is love.
Man lives by symbols; and it is probably true that it would not be possible to live in any real sense without them. Suppose that two people want to exchange ideas on a subject. Their ideas are 'spirtual' -- or at least non-material -- as is the desire to share them. These ideas, then, can only be shared through some symbolic device. The individuals can speak or write to each other. The spoken word is an outward and audible symbol, the written word an outward and visible symbol of the ideas conveyed by it. In the absence of symbolic device, the two minds will never meet. Indeed there are those who would posit that this capacity for symbolization is what distinguishes man from the rest of creation.
Man's conquest of the world undoubtedly rests on the supreme development of his brain, which allows him to synthesize, delay, and modify his reactions by the interpolation of symbols in the gaps and confusions of direct experience, and by means of verbal signs to add the experience of other people to his own. [F.W. Dillistone, Christianity and Symbolism, p. 23].
In the sacraments the Christian community has its peculiar symbols which are both formative of the community and necessary to its life. These symbols are the means of communicating to its people the reality and experience of the Risen Christ. Each of these sacraments is in a special way an extension of the Incarnation into the various needs and concerns of human life.....
James M. Jensen, Evanston, Illinois, May, 1972, from "A Five-Week Adult Study Course on Christian Initiation," a Project Submitted to the Faculty of Seabury-Western Theological Seminary