Wherefore gird up the loins of your mind, be sober, and hope to the end for the grace that is to be brought unto you at the revelation of Jesus Christ. 1 Peter 1:13. AG 327.1
Few realize that it is a duty to exercise control over the thoughts and imaginations. It is difficult to keep the undisciplined mind fixed upon profitable subjects. But if the thoughts are not properly employed, religion cannot flourish in the soul. The mind must be preoccupied with sacred and eternal things, or it will cherish trifling and superficial thoughts. Both the intellectual and the moral powers must be disciplined, and they will strengthen and improve by exercise. AG 327.2
In order to understand this matter aright, we must remember that our hearts are naturally depraved, and we are unable of ourselves to pursue a right course. It is only by the grace of God, combined with the most earnest effort on our part, that we can gain the victory.25Counsels to Parents, Teachers, and Students, 544. AG 327.3
Every wrong tendency may be, through the grace of Christ, repressed, not in a languid, irresolute manner, but with firmness of purpose, with high resolves to make Christ the pattern. Let your love go out for those things that Jesus loved, and be withheld from those things that will give no strength to right impulses. With determined energy seek to learn, and to improve the character every day. You must have firmness of purpose to take yourself in hand and be what you know God would be pleased to have you.26That I May Know Him, 135. AG 327.4
The intellect, as well as the heart, must be consecrated to the service of God. He has claims upon all there is of us. The follower of Christ should not indulge in any gratification, or engage in any enterprise, however innocent or laudable it may appear, which an enlightened conscience tells him would abate his ardor or lessen his spirituality. Every Christian should labor to press back the tide of evil, and save our youth from the influences that would sweep them down to ruin. May God help us to press our way against the current.27Counsels to Parents, Teachers, and Students, 544. AG 327.5