Hypnotism hath a weak influence over bodies, but hath no result, but the power of the kingdom of God is great. If thou canst, endeavor to obtain a share of that power.

‘Abdu’l-Bahá, Tablets of ‘Abdu’l-Bahá, Vol. I, p. 169

What comes under the heading of psychic practices ‘Abdu’l-Bahá has warned us against; but any form of auto-suggestion or hypnotism which is used by medical science and by properly qualified physicians we are free to take advantage of, if we feel that the doctor using such practices is qualified and will not abuse his rights.

Shoghi Effendi, Lights of Guidance, p. 288