Spiritual concepts
Samadhi

Samadhi is a term used in Buddhism that is synonymous with the concept of Balance.
Asvaghosha - The Awakening of Faith in the Mahayana translated by D T Suzuki
Samadhi is commonly rendered by ecstasy, trance, concentration, or meditation, all of which are misleading or incorrect. The term means mental equilibrium, and the reasons why Buddhism recommends the practising of it are, that it helps us in keeping our minds free from disturbance, that it prepares us for a right comprehension of the nature of things, and that it subjugates momentary impulses, giving us time for deliberation.

Ecstasy or trance instead of producing those benefits, will lead us to a series of hallucinations, and this is the very opposite of mental quietude.
It is definitively not, [as Rhys Davids has postulated], the same as faith in christianity, for all the above stated reasons.
It may be worth adding that both Christianity and Islam have no terms for many of these mystic concepts as they do not encourage spiritual experience.
Observations
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