John the Apostle
Revelation 14:5BSB·traditional attribution

And no lie was found in their mouths; they are blameless.

Matthew Henry Presbyterian @wholebiblehenry

Here we have one of the most pleasing sights that can be viewed in this world - the Lord Jesus Christ at the head of his faithful adherents and attendants. Here observe, 1. How Christ appears: as a Lamb standing upon mount Zion. Mount Zion is the gospel church. Christ is with his church and in the midst of her in all her troubles, and therefore she is not consumed.

Commenting on Revelation 14:1-5

John Gill Reformed Baptist @doctorgill

And in their mouth was found no guile,.... Or "a lie", as the Complutensian edition, the Alexandrian copy, the Vulgate Latin, and all the Oriental versions read; by which may be meant idolatry, for idols and idolatrous practices are often called lies, and lying vanities; see Jer 16:19; and the sense is, that the superstition and idolatry of the church of Rome were not among...

Albert Barnes Presbyterian @notesbybarnes

Verse 5. And in their mouth was found no guile. No deceit, fraud, hypocrisy. They were sincerely and truly what they professed to be--the children of God. This is the last characteristic which is given of them as redeemed, and it is not necessary to say that this is always represented as one of the characteristics of the true children of God. .