Joseph Benson's Commentary of the Old and New Testaments - Matthew 26:65
Matthew 26:65. Then the high-priest rent his clothes Though the high-priest was forbidden to rend his clothes, (that is, his upper garments,) in some cases, where others were allowed to do it, (Leviticus 10:6; and Leviticus 21:10;) yet in case of blasphemy, or any public calamity, it was thought allowable, 2 Kings 19:1; 1Ma 11:71 ; Caiaphas, therefore, by this action, expressed in the strongest and most artful manner, his horror at hearing so mean and vile a person as he thought Jesus to... read more
Albert Barnes' Notes on the Whole Bible - Matthew 26:65
Then the high priest rent his clothes - The Jews were accustomed to rend their clothes as a token of grief. This was done often as a matter of form, and consisted in tearing a particular part of the garment reserved for this purpose. It was not lawful for the high priest to rip his clothes, Leviticus 10:6; Leviticus 21:10. By that was probably intended the robes of his priestly office. The garment which he now tore was probably his ordinary garment, or the garments which he wore as president of... read more