Pray, read the Bible, and suffer.
Pretty simple.
Here’s how Luther explains it:
Moreover, I want to point out to you a correct way of studying theology, for I have had practice in that. If you keep to it, you will become so learned that you yourself could (if it were necessary) write books just as good as those of the fathers and councils, even as I (in God) dare to presume and boast, without arrogance and lying, that in the matter of writing books I do not stand much behind some of the fathers. Of my life I can by no means make the same boast. This is the way taught by holy King David (and doubtlessly used also by all the patriarchs and prophets) in the one hundred nineteenth Psalm. There you will find three rules, amply presented throughout the whole Psalm. They are Oratio, Meditatio, Tentatio.
1. Oratio: Prayer
Firstly, you should know that the Holy Scriptures constitute a book which turns the wisdom of all other books into foolishness, because not one teaches about eternal life except this one alone. Therefore you should straightway despair of your reason and understanding. With them you will not attain eternal life, but, on the contrary, your presumptuousness will plunge you and others with you out of heaven (as happened to Lucifer) into the abyss of hell. But kneel down in your little room [Matt. 6:6] and pray to God with real humility and earnestness, that he through his dear Son may give you his Holy Spirit, who will enlighten you, lead you, and give you understanding.
Thus you see how David keeps praying in the above-mentioned Psalm, “Teach me, Lord, instruct me, lead me, show me,” and many more words like these. Although he well knew and daily heard and read the text of Moses and other books besides, still he wants to lay hold of the real teacher of the Scriptures himself, so that he may not seize upon them pell-mell with his reason and become his own teacher. For such practice gives rise to factious spirits who allow themselves to nurture the delusion that the Scriptures are subject to them and can be easily grasped with their reason, as if they were Markolf or Aesop’s Fables, for which no Holy Spirit and no prayers are needed.2: Meditatio: Read and meditate on the Bible
Secondly, you should meditate, that is, not only in your heart, but also externally, by actually repeating and comparing oral speech and literal words of the book, reading and rereading them with diligent attention and reflection, so that you may see what the Holy Spirit means by them. And take care that you do not grow weary or think that you have done enough when you have read, heard, and spoken them once or twice, and that you then have complete understanding. You will never be a particularly good theologian if you do that, for you will be like untimely fruit which falls to the ground before it is half ripe.
Thus you see in this same Psalm how David constantly boasts that he will talk, meditate, speak, sing, hear, read, by day and night and always, about nothing except God’s Word and commandments. For God will not give you his Spirit without the external Word; so take your cue from that. His command to write, preach, read, hear, sing, speak, etc., outwardly12 was not given in vain.
3: Tentatio: Suffering
Thirdly, there is tentatio, Anfechtung. This is the touchstone which teaches you not only to know and understand, but also to experience how right, how true, how sweet, how lovely, how mighty, how comforting God’s Word is, wisdom beyond all wisdom.
Thus you see how David, in the Psalm mentioned, complains so often about all kinds of enemies, arrogant princes or tyrants, false spirits and factions, whom he must tolerate because he meditates, that is, because he is occupied with God’s Word (as has been said) in all manner of ways. For as soon as God’s Word takes root and grows in you, the devil will harry you, and will make a real doctor of you, and by his assaults will teach you to seek and love God’s Word. I myself (if you will permit me, mere mouse-dirt, to be mingled with pepper) am deeply indebted to my papists that through the devil’s raging they have beaten, oppressed, and distressed me so much. That is to say, they have made a fairly good theologian of me, which I would not have become otherwise. And I heartily grant them what they have won in return for making this of me, honor, victory, and triumph, for that’s the way they wanted it.
There now, with that you have David’s rules. If you study hard in accord with his example, then you will also sing and boast with him in the Psalm, “The law of thy mouth is better to me than thousands of gold and silver pieces” [Ps. 119:72]. Also, “Thy commandment makes me wiser than my enemies, for it is ever with me. I have more understanding than all my teachers, for thy testimonies are my meditation. I understand more than the aged, for I keep thy precepts,” etc. [Ps. 119:98–100]. And it will be your experience that the books of the fathers will taste stale and putrid to you in comparison. You will not only despise the books written by adversaries, but the longer you write and teach the less you will be pleased with yourself. When you have reached this point, then do not be afraid to hope that you have begun to become a real theologian, who can teach not only the young and imperfect Christians, but also the maturing and perfect ones. For indeed, Christ’s church has all kinds of Christians in it who are young, old, weak, sick, healthy, strong, energetic, lazy, simple, wise, etc.
If, however, you feel and are inclined to think you have made it, flattering yourself with your own little books, teaching, or writing, because you have done it beautifully and preached excellently; if you are highly pleased when someone praises you in the presence of others; if you perhaps look for praise, and would sulk or quit what you are doing if you did not get it—if you are of that stripe, dear friend, then take yourself by the ears, and if you do this in the right way you will find a beautiful pair of big, long, shaggy donkey ears. Then do not spare any expense! Decorate them with golden bells, so that people will be able to hear you wherever you go, point their fingers at you, and say, “See, See! There goes that clever beast, who can write such exquisite books and preach so remarkably well.” That very moment you will be blessed and blessed beyond measure in the kingdom of heaven. Yes, in that heaven where hellfire is ready for the devil and his angels. To sum up: Let us be proud and seek honor in the places where we can. But in this book the honor is God’s alone, as it is said, “God opposes the proud, but gives grace to the humble” [1 Pet. 5:5]; to whom be glory, world without end, Amen.
Luther’s Works (American Edition) 34:285-288
