The ultimate generating symbol
“In India, the most common ultimate symbol is of the phallus, or lingam, as they call it, of the generating god penetrating the vagina, or the yoni, as they call it, of the Goddess. In contemplating this symbol, you are contemplating the generating moment itself of all life. The entire mystery of the generation of life is symbolically contemplated in that sign.
You see, the sexual mystery in India, and in most of the world, is a holy mystery. It is the mystery of the generation of life. The act of generating a child is a cosmic act and is to be understood as holy. And so the symbol that most immediately represents this mystery of the pouring of the energy of life into the field of time is the lingam and the yoni, the male and female powers in creative conjunction.”
– from Joseph Campbell with Bill Moyers, The Power of Myth, VI.The Gift of the Goddess