Meditation is central to all spiritual life, whatever be the religion one follows. Swami Ritajananda, who had wide experience with spiritual seekers both in India and abroad, has very clearly set forth the principles and practice of meditation. The part played by the guru and the mantra are lucidly set forth. Quotations are also given from the Scriptures to explain the various factors involved in meditation.
If you want to be a Yogi, you must be free, and place yourself in circumstances where you are alone and free from all anxiety. One who desires a comfortable and nice life and, at the same time, wants to realize the Atman is like the fool who, wanting to cross the river, caught hold of a crocodile mistaking it for a log of wood.
-Swami Vivekananda