Revelation 14:5
And in their mouth was found no guile: for they are without fault before the throne of God. (Revelation 14:5)
Guile.
Gr. dolos, “deceit,” “subtlety,” “fraud,” “guile.” Textual evidence attests (cf. p. 10) the reading pseudos, “falsehood,” “lie.” The gospel of Jesus Christ changes sinful, erring man into one who has no pretense, no make-believe, no deceit, no sin.
Was found.
The form of the Greek verb suggests that a certain point of time is under consideration. At that point of time investigation proves the 144,000 to be faultless. This does not mean that they had never erred, but that by the grace of God they had overcome all defects of character.
Without fault.
 Gr. amōmos, “faultless,” “blameless” (see on Eph. 1:4; cf. COL 69; TM 506).
Before the throne.
Textual evidence attests (cf. p. 10) the omission of this phrase.