There is a psychotherapist-patient privilege.

Crawford v. Washington, 541 U.S. 36, 68 (2004) ("Whatever else the term ['testimonial'] covers, it applies at a minimum to prior testimony at a preliminary hearing, before a grand jury, or at a former trial").The U.S. Supreme Court and other courts have said that statements made in formal judicial proceedings are "testimonial" and are therefore subject to the constraints imposed on the use of testimonial hearsay in criminal trials by the Confrontation Clause of the Sixth Amendment to the U.S. Constitution.

Fed. R. Evid. 702 ("If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise, if (1) the testimony is...The trial court must act as an independent gatekeeper. The trial court can admit expert or scientific evidence only if it finds that scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise, if (1) the testimony is based upon sufficient facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case.

Levin v. United States, 119 U.S.App.D.C. 156,, 338 F.2d 265, pin? (D.C. Cir. 1964) (religiously-motivated pattern of conduct does not constitute habit and is therefore inadmissible character evidence).Religiously-motivated behavior does not constitute "habit" for purposes of Rule 406.