From the Word
3 O LORD, in the morning thou dost hear my voice; in the morning I prepare a sacrifice for thee, and watch. 7 But I through the abundance of thy steadfast love will enter thy house, I will worship toward thy holy temple in the fear of thee. 8 Lead me, O LORD, in thy righteousness because of my enemies; make thy way straight before me. 11 But let all who take refuge in thee rejoice, let them ever sing for joy; and do thou defend them, that those who love thy name may exult in thee. 12 For thou dost bless the righteous, O LORD; thou dost cover him with favor as with a shield.
Psalm 5:3, 7-8, 11-12, RSV
Here we are told when and what joy is, namely, confidence and a good conscience resting in the mercy of God. They that have had experience in these things say that there is no joy above that of a pure conscience, nor any sorrow greater than that of a guilty and troubled one. A pure and joyful conscience comes in no other way than by looking steadfastly to the mercy of God. In the former part of this verse he describes the joy in tribulation; in the latter part the joy of prosperity, which cannot be true and sincere unless it be a rejoicing in God only. This verse briefly makes a distinction between prosperity and adversity. It is impossible that he who does not trust in the Lord should not be filled with sorrow when tribulation comes upon him. He who is in sorrow cannot but continually murmur, because there is no praising of God without joy of heart, and this sorrowful and impatient murmurer must displease God and be more and more forsaken of him.
On the other hand it is impossible that he should not rejoice who trusts in God. If the whole world should burst upon the head of such a one he would stand unmoved amid the falling ruins. He who is joyful in such hope cannot but think well of God, exult in his praise, and encourage himself in him. The man who thus rejoices is patient, happy and in a state to be protected of God. Nor will such a one rejoice, hope and exult in vain, for God will preserve him. If then thy soul be sad and cast down, begin some joyful song or psalm or something that brings thy God to thy memory and thou wilt find relief and wilt prove that the counsel of the wise man it good: “In the day of evil be not unmindful of good things.”
By the name of the Lord we may understand Jesus Christ, or Father, Son and Holy Spirit. All these are names of God. They who love the name of Jesus love the salvation of God, the truth, the mercy and the wisdom of God; all these are included in the name of the Lord. If a man love these he must of necessity love the name of the Lord.
Luther, Martin, and John Sander. Devotional Readings from Luther’s Works for Every Day of the Year. Augustana Book Concern, 1915, pp. 399–400.