“The promises of God’s grace provide the power that makes the demands of God’s holiness an experience of freedom rather than fear. Peter described the freeing power of God’s promises like this: ‘Through [His precious and very great promises] you may become partakers of the divine nature, having escaped from the corruption that is in the world because of sinful desire’ (2 Peter 1:4). In other words, when we trust the promises of God, we sever the root of corruption by the power of a superior promise.
Therefore we should pray for each other the way Jesus prays for us in John 17:17: ‘Sanctify them in the truth; your word is truth’. There is no abiding joy without holiness, for the Scripture says, ‘Strive…for the holiness without which no one will see the Lord’ (Hebrews 12:14). How important, then, is the truth that sanctifies! How crucial is the Word that breaks the power of counterfeit pleasures! And how vigilant we should be to light our paths and load our hearts with the Word of God! ‘Your word is a lamp to my feet and a light to my path’ (Psalm 119:105). ‘I have stored up your word in my heart, that I might not sin against you’ (v. 11; cf. v. 9).
John Piper – Desiring God pp. 149-150