Consider first, that besides the evil of sensuality, which must be mortified in order to subdue the concupiscence of the flesh, there is another dangerous evil that must also be mortified in order to subdue the concupiscence of the eyes; and that is, the vice of curiosity, which St. Augustine (Confessions L. x., c. 35,) supposes to be understood by this name. A dangerous evil indeed, and the mother of many evils; which makes men busy themselves about things either hurtful, or at least nothing at all to their purpose, whilst they neglect things profitable and necessary, yea the only thing necessary. Alas! how many things are there that men take much pains to inquire into, which are dangerous to their souls? How many which are absolutely useless and unprofitable, and which answer no manner of end, either of the glory of God or of their own or neighbour's good? And how much loss is here of their precious time! What dissipation of thought! What distractions in prayer! What forgetfulness of God and eternity! What an enslaving of the soul to meet toys and vanities! And what account shall they be able to give at the last day, of a life spent so unprofitably, so unworthily of the great end for which they came hither; and so perversely, because so contrary to the holy will and law of their maker? Ah, the dismal consequence of indulging this unhappy curiosity!
Consider 2ndly, the particulars in which we must mortify the lust of the eyes, if we hope to keep the soul pure, and to prevent death from coming in at those windows. We must turn our eyes away from vanity; and much more from such objects as allure the soul to impure love: an unguarded glance of an eye has a thousand and a thousand times been the death of the soul. unhappy they who are ever indulging their curiosity in looking after such dangerous objects! And much more unhappy they, who affect by their light carriage and indecent dress to draw the eyes and hearts of others to lust; as also with relation to the reading of all such books, as being either lewd, or profane, or irreligious, tend to debauch the soul, and to draw her into sin. In which number romances, play-books, and such like, are certainly to be comprised; because they only serve to heighten the passions, to soften the soul, and to dispose her to carnal love, and to shut out from her the spirit of devotion and of the love of God.
Consider 3rdly, the necessity of mortifying in like manner the ears; since those also are an avenue through which, if not well guarded, death oftentimes makes its way into the soul. This branch of curiosity must be corrected, first by stopping the ears to all loose narrations, jests, or songs - all which are apt to convey a mortal poison into the soul - secondly, by restraining them from hearkening to scandal and detraction, with danger of either taking pleasure in it, or countenancing and encouraging so great an evil; thirdly, by keeping a guard upon them, to prevent their taking in a still greater infection, by hearkening to irreligious and impious discourses, which strike at the deity and his revealed truths, or tend to the discouraging of virtue or promoting of vice. In a word, the Christian that would save his soul must ever have a guard upon himself in all company and conversation, lest the curiosity of his ears induce him to hearken with pleasure to any such speeches or words as may let in the corruption of sin into his heart.
Conclude ever to watch and pray against the evil of curiosity, which has so many ways of poisoning the soul. But it thou wouldst indulge the desire of knowledge, (which is so natural to man,) let it be by inquiring into useful truths, and such as may serve to bring thee to the sovereign truth. 'But woe to them that inquire of men after many curious things, and at the same time are but little curious of knowing the way to serve God!' - Kempis.