Buddha Shakyamuni predicted Guru Padmasambhava's

Guru Rinpoche incarnated as a fully enlightened being. Through his form, primordial wisdom manifested in the world to benefit all sentient beings.

Buddha Shakyamuni actually predicted Guru Padmasambhava's appearance in several different sutras and tantras contain clear predictions of his coming and activities.In the Mahaparinirvana Sutra, Buddha Shakyamuni announced his parinirvana to the students who were with him at the time. Many of them, particularly Ananda, the Buddha's cousin and personal attendant, were quite upset upon hearing this. So Buddha turned to Ananda and told him not to worry. "Eight years after my parinirvana, a remarkable being with the name Padmasambhava will appear in the center of a lotus and reveal the highest teaching concerning the ultimate state of the true nature, bringing great benefit to all sentient beings. Buddha Shakyamuni also said Padmasambhava would be an emanation of Buddha Amitabha and Avalokitésvara and referred to him as the embodiment of all the buddhas of the three times. Many prophecies indicate that Guru Rinpoche would be a fully enlightened buddha, appearing in this world to help sentient beings.

For the most part, Buddha Shakyamuni presented Hinayana and Sutra Mahayana teachings, while Guru Padmasambhava taught the Vajrayana. Both revealed the complete and perfect path to awakening so that individuals of all capacities would be able to benefit. The absolute level of the Buddha's teaching is beyond conception. If it did not go beyond the conceptual level, there would be no need to change our normal way of understanding things. To help us realize the primordial nature, Buddha Shakyamuni taught again and again that we must transcend clinging to ordinary dualistic conceptions, narrow attitudes, close mindedness, traditional rules, beliefs and limitations.

The ultimate meaning of the highest teaching is not readily understood by sentient beings. This is why Buddha Shakyamuni kept silent for forty-nine days after his enlightenment. He thought, "I have realized the most profound and subtle dharma, the clear light free of all complexity. However, this is much too deep for normal people to understand. Therefore, I will remain silent." He knew how hard it would be to communicate the truth of his insight. Although he eventually taught tirelessly for forty-five years, his first thought reflects the extraordinary nature of the state into which he had awakened relative to mundane ideas and conceptions.

Sutra is a Sanskrit word meaning "condensed or summarized." Scripture bearing this title indicates that these teachings were directly communicated in the world in order to provide a clear understanding of both the relative and absolute aspects of our existence. They provide knowledge with which a practitioner can realize buddhahood.

Most of Buddha Shakyamuni's teachings address ordinary beings and offer a direct means of understanding the nature of our experience. It is a non-esoteric view which appeals to common logic, with tenets that can be verified by close observation of the elements which constitute our everyday world. With this knowledge, you can move toward enlightenment. This is the basic intention of Sutra Mahayana.

The Vajrayana is also known as Tantra. Tantric teachings are based upon the Sutra Mahayana, but offer additional means and methods. Vajrayana practices encourage us to take a deeper look at our perceptions, to understand the primordial nature and learn to maintain mind in that state. The Sutras may be called general teachings which clarify the nature of conditional mind and perception, while the Vajrayana reveals the secret structure of phenomena and is for more advanced practitioners. Although they share the same foundation, the Vajrayana goes further toward understanding transcendental reality. To practice both Sutra and Tantra together can bring enlightenment within this life, even within a very short period of time. Such acceleration distinguishes Vajrayana techniques.

The Buddha only gave Vajrayana teachings privately, to select groups of disciples. Because the essence and even the form of these higher teachings is beyond common conception, they are also known as secret teachings. After the Buddha entered mahaparinirvana, these secret doctrines were preserved by a host of wisdom dakinis.

http://www.padmasambhavastupa.org/padmasambhava.html