saddhā - faith, confidence.
A Buddhist is said to have faith if "he believes in the Perfect One's (the Buddha's) Enlightenment" (M 53; A.V, 2), or in the Three Jewels (s. ti-ratana), by taking his refuge in them (s. ti-sarana). His faith, however, should be "reasoned and rooted in understanding" (ākāravatā saddhā dassanamūlika; M. 47), and he is asked to investigate and test the object of his faith (M. 47, 95). A Buddhist's faith is not in conflict with the spirit of inquiry, and "doubt about dubitable things" (A. II, 65; S. XLII, 13) is admitted and inquiry into them is encouraged. The 'faculty of faith' (saddhindriya) should be balanced with that of wisdom (paññindriya; s. indriya-samatta). It is said: "A monk who has understanding, establishes his faith in accordance with that understanding" (S. XLVIII, 45). Through wisdom and understanding, faith becomes an inner certainty and firm conviction based on one's own experience.
Faith is called the seed (Sn. v. 77) of all wholesome states because, according to commentarial explanations, it inspires the mind with confidence (okappana, pasāda) and determination (adhimokkha), for 'launching out' (pakkhandhana; s. M. 122) to cross the flood of samsāra.
Unshakable faith is attained on reaching the first stage of holiness, 'stream-entry' (sotāpatti, s. ariyapuggala), when the fetter of sceptical doubt (vicikicchā; s. samyojana) is eliminated. Unshakable confidence (avecca-pasāda) in the Three Jewels is one of the characteristic qualities of the Stream-winner (sotāpannassa angāni, q.v.).
Faith is a mental concomitant, present in all karmically wholesome, and its corresponding neutral, consciousness (s. Tab. II). It is one of the 4 streams of merit (puññadhārā, q.v.), one of the 5 spiritual faculties (indriya, q.v.), spiritual powers (bala, q.v.), elements of exertion (padhāniyanga, q.v.) and one of the 7 treasures (dhana, q.v.).
See Faith in the Buddha's Teaching, by Soma Thera (WHEEL 262). "Does Saddhā mean Faith? by Ñānamoli Thera (in WHEEL 52/53).