Charles H. Spurgeon on Psalms 17:4

"By the word of thy lips," etc. It is a great relief against temptations to have the word ready. The word is called, "The sword of the Spirit." Ephesians 6:17. In spiritual conflicts there is none like to that. Those that ride abroad in time of danger, will not be without a sword. We are in danger, and had need handle the sword of the Spirit. The more ready the Scripture is with us, the greater advantage in our conflicts and temptations. When the devil came to assault Christ, he had Scripture ready for him, whereby he overcame the tempter. The door is barred upon Satan, and he cannot find such easy entrance when the word is hid in our hearts, and made use of pertinently. "I write unto you, young men, because ye are strong." Where lies their strength? "And the word of God abideth in you, and ye have overcome the wicked one." 1 John 2:14. Oh, it is a great advantage when we have the word, not only by us, but in us, engrafted in the heart; when it is present with us, we are more able to resist the assaults of Satan. Either a man forgets the word, or hath lost his affection to it, before he can be drawn to sin. —Thomas Manton.