Imam on various occasions in this regard said as following:
The teaching of the Book and Wisdom will be impossible unless purgation comes first. You should purge your 'selves' from all contaminations. The worst one is the contamination of the 'self' with selfish and animal desires. (June 2, 1981)
Those who are trying to train others in this world should first purge themselves. Those who seek to rule over human beings should be purged and purified if they do not want to rebel (against God) and to not commit satanic deeds; The Ordainment is for this purpose. Purification for rulers, government officials, kings and for the presidents, is more necessary than for ordinary people. (June 2, 1981)
There are two sides and dimensions to mankind. The spiritual side and the material side. The material aspect is what we observe, that which exists in this world. They are these materials that we witness. The spiritual side is another aspect beyond this world, Imam Khomeini explained (June 24, 1979)
All monotheistic schools of thought, in action with Islam, as the superior one, are seeking to train people in such a way that material gains do not act as obstacles for spirituality, although they (the divine religions) are involved with materiality as well. They seek to bring material gains under the service of spirituality. While the religions pay heed to the material and the world, they attract people towards spirituality and liberate them from the darkness of the material at the same time. (July 27, 1979)
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