śraddhā [saddhā] faith, confidence. Śraddhā is devotion to the Buddha, the Dharma and the Saṅgha, based on conviction. Asaṅga defines śraddhā as serene joy at good qualities, desire to achieve an object and conviction. The mind is dictated by craving and hence is attached to objects which are the cause of pleasure. No wonder, it is unable to realise the reality. The power of confidence overcomes craving and takes the aspirant to the ultimate goal, hence it is an important factor in the practice of the Insight Meditation. Confidence is attained when doubt vanishes and the stage of 'stream-entry' is reached. Belief and clarity of mind are the essential features of confidence power. Confidence is not a blind faith; it is a wholesome mental factor. Unless the power of confidence is coupled with wisdom it does not give the desired result. It enables the aspirant to cross over the saṃsāra by enforcing the mind with determination and strength.

 

Buddhānusmṛti - A Glossary of Buddhist Terms

Aṭṭhasālinī. I. 173, 225-226.

śraddhā

(Skt,; Pāli, saddhā). An attitude of faith, trust, or confidence, especially in the Buddha and his teachings. Faith is a prerequisite for embarking on the Eightfold Path, but it must be tempered by critical reflection and tested against one's own experience. In general, there is no doctrine of ‘salvation by faith’ in Buddhism, and blind faith is not regarded as a virtue: instead each person must cultivate insight and understanding (prajñā) into the Four Noble Truths. Some forms of Pure Land Buddhism, however, do teach that rebirth in a Pure Land (or heaven) can be obtained through faith alone.

A Dictionary of Buddhism, Oxford University Press, 2003, 2004 (which is available in electronic version from answer.com)