An Eye For An Eye

Illud vero quid significat, quod in hac lege oculum pro oculo dari jubetur? Oculus enim est quisque doctor , tanquam vitae demonstrans iter. Idem autem si intentionem auditoris per aliquam perniciosam doctrinam conetur exstinguere, si oculum laedet animam, et intellectum ejus turbet, auferatur necesse est ab Ecclesia preasulatu, et intellectus ejus turbulentus ac ferox, qui scandalum fidei generat, projiciatur. Sed etsi quis dentem laesit auditoris, per quem Scripturarum cibos comminuebat, et dividens spiritualiter distinguebat, ut subtilem ex his ad interiora animae transmitteret sensum; quiquis ergo hujusmodi evellens dentem conatur a corpore praecidere, auferatur dens illi. De talibus enim dicitur : Dentes peccatorum contrivisti, siquidem et manus pro manu, et pes pro pede deposcitiur. Manus est actio operantis, pes est per quem inceditur ad bona opera vel mala. Praecidatur ergo ille scandalum facit, non solum in fide, sed etiam in actibus, qui per manum significantur, aut offendiculum praebet, quo pedes intelliguntur. Recipiat etiam combustionem qui combussit, et gehennae fraternam tradidit animam. Per quae signacula ostenditur ut iste percussor, omnibus detruncatus membris, a corpore excidatur Ecclesiae, ut caeteri videntes timorem habeant, et non faciant similiter.  Sanctus Isidorus Hispalensis, Quaestiones in Vetus Testamentum, Caput XXXVI

What does it mean in this law when it is commanded, 'An eye for an eye?' 1 The eye is as a teacher, as that which shows the way of life. Yet if the same tries to extinguish the understanding of the hearer by some wicked teaching, if he harms the eye of the soul, and troubles the intellect, it is necessary that he should be removed from the Church and his troublesome and wild mind, which is a cause of scandal, cast out. But if someone harms the teeth of the hearer, by which he feeds on the bread of Scripture and separating it spiritually distinguishes, that the lofty meaning pass into the interior of his soul, whoever then tries to remove the teeth from the body, shall loose his own teeth. For concerning this it is said, 'You crushed the teeth of the sinners.' 2 And likewise a hand for a hand and a foot for a foot is demanded. 1 The hand is the worker of the deed, and the foot is that by which one is brought to good or evil deeds. He shall be cut off, then, who causes scandal, not only in the faith, but in his acts, which the hand signifies, or when he gives offence, which we understand by the feet. And he shall receive fire who brings fire, 3 and gives a brother's soul to hell. By which signs it is shown that he who is a killer, from all its members severed, shall be cut off from the body of the Church, so that others seeing fear it, and do not do the same. Saint Isidore of Seville, Questions on the Old Testament, Chapter 36 1 Exod 21.24 2 Psalm 3.8 3 Exod 21.25