“Even so ye also outwardly appear righteous unto men, but within ye are full of hypocrisy and iniquity.”
Matthew 23:28 — Greek Interlinear
Church Fathers on Matthew 23:28
As above they are said to be 'full of extortion and excess,' so here they are 'full of hypocrisy and iniquity,' and are likened to dead men’s bones, and all uncleanness.
Justly are the bodies of the righteous said to be temples, because in the body of the righteous the soul has dominion, as God in His temple; or because God Himself dwells in righteous bodies. But the bodies of sinners are called sepulchres of the dead, because the sinner’s soul is dead in his body; for that cannot be deemed to be alive, which does no spiritual or living act.
Sepulchres are whitened with lime without, and decorated with marble painted in gold and various colours, but within are full of dead men’s bones. Thus crooked teachers who teach one thing and do another, affect purity in their dress, and humility in their speech, but within are full of all uncleanness, covetousness, and lust.