Note:
Luther here uses ‘contemplation’ and ‘meditation’ as synonyms. But the main point here is that meditation, by whatever name, is of more benefit to us than any amount of external works can be. Meditation changes our hearts. Even just 15 minutes of real meditation on Christ’s betrayal, arrest, trials, torture, crucifixion is way more beneficial than any spiritual disciplines, says Luther.

Quote:
“We say without hesitation that he who contemplates God’s sufferings for a day, an hour, yes, only a quarter of an hour, does better than to fast a whole year, pray a psalm a day, yes, better than to hear a hundred masses. This meditation changes a man’s being and, almost like baptism, gives him a new birth.”  (page 11)

Source: Luther, Martin. “A Meditation on Christ’s Passion” (1519) Luther’s Works Vol. 42. Philadelphia: Fortress Press, 1969.