V.T.N.: "Guru Deva, what is the difference between 'japa' and 'dhyana' ?
Babaji: "Japa is the repetition of the mantra of a Devata. Dhyana is meditation on His or Her form and attributes. It is the keeping up a continuous flow of one idea of God."
V.T.N.: "What is japa sahita dhyana and japa rahita dhyana?"
Babaji: "The aspirant is repeating the mantra and at the same time he is meditating on the form of his ishta Devata. A Krishna bhakta repeats the mantra 'Aum namo bhagavate vasudevaya' and at the same time he visualizes the rupa of the Lord, Sri Krishna. This is japa sahita dhyana. In japa rahita dhyana the devotee continues his japa for sometime along with the meditation and afterwards the japa drops by itself and he is established in meditation only."