1. To be jealous of what you see to be good, and to be envious of those who are better than yourself, seems, beloved brethren, in the eyes of some people to be a slight and petty wrong; and, being thought trifling and of small account, it is not feared; not being feared, it is contemned; being contemned, it is not easily shunned: and it thus becomes a dark and hidden mischief, which, as it is not perceived so as to be guarded against by the prudent, secretly distresses incautious minds. But, moreover, the Lord bade us be prudent, and charged us to watch with careful solicitude, lest the adversary, who is always on the watch and always lying in wait, should creep stealthily into our breast, and blow up a flame from the sparks, magnifying small things into the greatest; and so, while soothing the unguarded and careless with a milder air and a softer breeze, should stir up storms and whirlwinds, and bring about the destruction of faith and the shipwreck of salvation and of life.  Therefore, beloved brethren, we must be on our guard, and strive with all our powers to repel, with solicitous and full watchfulness, the enemy, raging and aiming his darts against every part of our body in which we can be stricken and wounded, in accordance with what the Apostle Peter, in his epistle, forewarns and teaches, saying, “Be sober, and watch; because your adversary the devil, as a roaring lion, goeth about seeking any one to devour.”1    1 Pet. v. 8.

I. ZELARE quod bonum videas et invidere melioribus 0639A leve apud quosdam et modicum crimen videtur, fratres dilectissimi; dumque existimatur leve esse et modicum, non timetur; dum non timetur, contemnitur; dum contemnitur, non facile vitatur, et fit caeca et occulta pernicies: quae, dum minus perspicitur ut caveri a providentibus possit, improvidas mentes latenter affligit. Porro autem Dominus prudentes esse nos jussit, et cauta sollicitudine vigilare praecepit, ne adversarius vigilans semper et semper insidians, ubi in pectus obrepserit , de scintillis conflet incendia, de parvis maxima exaggeret, et, dum remissis et incautis leniore aura et flatu molliore blanditur, procellis ac turbinibus excitatis, ruinas fidei et salutis ac vitae naufragia moliatur. Excubandum est itaque, fratres dilectissimi, atque omnibus viribus elaborandum 0639B ut inimico saevienti et jacula sua in omnes corporis partes quibus percuti et vulnerari possumus, dirigenti sollicita et plena vigilantia repugnemus , secundum quod Petrus apostolus in Epistola sua praemonet et docet dicens: Sobrii estote et vigilate, quia adversarius vester diabolus tamquam leo rugiens circuit, aliquem devorare quaerens (I Pet. V, 8).