OSHO :- On Shivalinga

The Shivalinga is not a poetry, it is an experience. When the tidal flood of energy fills your whole body and your each and every cell is thrilled, then you will see around you a circle of light in the shape of Shivalinga and you will experience the substance of your entire body disappearing into that lightform. Only an egg-shaped form of light will remain. No eyes, no nose, no hands... all will disappear. This is the shape of your soul – this shining egg-shaped form.

The day you entered your mother’s womb it was a shivalinga-shaped point of light that actually entered; the body you acquired afterwards in the womb. When you leave the body, death happens – it has happened earlier also – the body, your form, will be left lying behind here and shivalinga, the lustrous point of light, will arise from it and set out on a new journey. What happened at the moment of conception, and happens again when you die, happens also at the ultimate state of sexual intercourse.

But you were not conscious at the moment of your conception, and in the moment of your death you will again be unconscious. In the moment of this sex I am talking about – and remember, this sex has nothing to do with the other, this has to do with your becoming a shivalinga of consciousness, breaking all barriers of the body within you – you will for the first time experience the form of your own self. And the bliss this self-form experiences with the existence, Tantra has called sexual intercourse.

This can happen in your aloneness as well as with someone else.

Osho : Nowhere To Go But In : Chapter 1