James 1:26

Thinketh himself to be religious

(δοκε θρησκος εινα). Condition of first class (ει-δοκε). Θρησκος (of uncertain etymology, perhaps from θρεομα, to mutter forms of prayer) is predicate nominative after εινα, agreeing with the subject of δοκε (either "he seems" or "he thinks"). This source of self-deception is in saying and doing. The word θρησκος is found nowhere else except in lexicons. Hatch (Essays in Biblical Greek, pp. 55-57) shows that it refers to the external observances of public worship, such as church attendance, almsgiving, prayer, fasting (Matthew 6:1-18). It is the Pharisaic element in Christian worship.While he bridleth not his tongue

(μη χαλιναγωγων γλωσσαν εαυτου). "Not bridling his own tongue." A reference to verse James 1:19 and the metaphor is repeated in James 3:12. This is the earliest known example of the compound χαλιναγωγεω (χαλινος, bridle αγο, to lead). It occurs also in Lucian. The picture is that of a man putting the bridle in his own mouth, not in that of another. See the similar metaphor of muzzling (φιμοω) one's mouth (Matthew 22:12 εφιμωθη).Deceiveth

(απατων). Present active participle from απατη (deceit). He plays a trick on himself.Religion

(θρησκεια). Later form of θρησκιη (Herodotus) from θρησκος above. It means religious worship in its external observances, religious exercise or discipline, but not to the exclusion of reverence. In the N.T. we have it also in Acts 26:5 of Judaism and in Colossians 2:18 of worshipping angels. It is vain (ματαιος, feminine form same as masculine) or empty. Comes to nothing.