“Blessed are those whose way is blameless, who walk in the law of the LORD!”
The 119th psalm is a long psalm, containing prayers, comforts, instructions, and thanks in great number. It is chiefly written to make us excited about God’s Word. It praises God’s Word throughout and warns us against both the false teachers and against boredom and contempt for the Word. Therefore, it is primarily to be counted among the psalms of comfort. Its primary concern is that we have God’s Word in its purity and hear it gladly. From this concern, then, come powerful prayers, instructions, thanks, prophecies, worship of God, suffering, and all that pleases God and grieves the devil. But where one despises the Word and is satiated by it, there all these cease. For where the Word is not purely taught, there is truly an abundance of prayers, instructions, comforts, worship, suffering, and prophecies—but totally false and condemned! For it is then only service to the devil, who is thus impure with all his heretics.
Beloved Father in heaven, You are blessed for granting us the Word of Your grace, in which You have revealed to us Your will concerning our salvation. Teach us to love Your Word, diligently to hear and willingly to learn it, that guided by this lamp our feet may walk in the way everlasting. Amen.
(from Reading the Psalms with Luther, pgs. 285-286)