The principle of mantra practice is transformation. Mantra is the form quality of emptiness, and the visualisation is the emptiness quality of form. Within Tantra the two are united as a means of transforming our dimension of being into that of the yidam. Mantra functions through repetition in terms of overwhelming the conceptual sphere – we become entirely engrossed with the quality sphere of the yidam in terms of light and sound.
There is no room for ‘me’ there. I have to let go of the ‘me project’. As soon as I let go of the ‘me project’, the yidam irradiates my experience with referenceless enjoyment in which there are no compulsory projects. One becomes the yidam and both sees and hears the world as the yidam.
Aro Encyclopaedia Index: Dzogchen and Tantra: question and answer session. Ngak'chang Rinpoche and Khandro Déchen