“May this tradition of the Conqueror, Losang Dragpa, That takes the emptiness explained in the Causal Vehicle (sutra), And the great bliss that is achieved through the Resultant Means (tantra), Conjoined with the essence of the collection of eighty-four thousand teachings flourish." — Extracted from His Holiness the Dalai Lama's Speech to the Second Gelug Conference (Dharamsala, India, December 6, 2000) at: www.dalailama.com.
Je Tsongkhapa (1357–1419) was a famous teacher of Tibetan Buddhism whose activities led to the formation of the Gelug school. He is also known by his ordained name Lobsang Drakpa or simply as Je Rinpoche.
Tsongkhapa heard Buddha's teachings from masters of all Tibetan Buddhist traditions, and received lineages transmitted in the major schools. His main source of inspiration was the Kadampa tradition, the legacy of Atisha.
Based on Tsongkhapa's teaching, the two distinguishing characteristics of the Gelug tradition are the union of sutra and tantra and emphasis on the step-by-step graduated way to enlightenment along the three principal aspects of the path (a genuine wish for liberation, generation of bodhicitta, and insight into emptiness).
In his two main treatises (lam rim chen mo and sngags rim chen mo), Tsongkhapa meticulously sets forth this graduated way and how one establishes oneself in the sutric and tantric paths.