Martin Luther here reminds us that being tempted is not a sin; it’s giving in that’s the sin. His reminder that we will constantly be under attack is always necessary, as well. The devil never takes a day off!
Also, Luther reminds us that the Lord’s Prayer is an excellent defense in time of temptation. When you know what it means (not just what it says) and you’re able to meditate on it, draw strength and comfort from it, and “lay hold” on it, as Luther says, then you have a valuable weapon against temptation. This is part of the reason we teach our young people the meaning of the Lord’s Prayer — so they can use it for themselves their whole lives long devotionally. Luther’s analogy of the devil having a snake’s head is also quite vivid and apt. Enjoy the quote.
From the Large Catechism:
107] To feel temptation is therefore a far different thing from consenting or yielding to it. We must all feel it, although not all in the same manner, but some in a greater degree and more severely than others; as, the young suffer especially from the flesh, afterwards, they that attain to middle life and old age, from the world, but others who are occupied with spiritual matters, that is, strong Christians, from the devil. 108]But such feeling, as long as it is against our will and we would rather be rid of it, can harm no one. For if we did not feel it, it could not be called a temptation. But to consent thereto is when we give it the reins and do not resist or pray against it.
109]Therefore we Christians must be armed and daily expect to be incessantly attacked, in order that no one may go on in security and heedlessly, as though the devil were far from us, but at all times expect and parry his blows. For though I am now chaste, patient, kind, and in firm faith, the devil will this very hour send such an arrow into my heart that I can scarcely stand. For he is an enemy that never desists nor becomes tired, so that when one temptation ceases, there always arise others and fresh ones.
110] Accordingly, there is no help or comfort except to run hither and to take hold of the Lord’s Prayer, and thus speak to God from the heart: Dear Father, Thou hast bidden me pray; let me not relapse because of temptations. Then you will see that they must desist, and finally acknowledge themselves conquered. 111] Else if you venture to help yourself by your own thoughts and counsel, you will only make the matter worse and give the devil more space. For he has a serpent’s head, which if it gain an opening into which he can slip, the whole body will follow without check. But prayer can prevent him and drive him back.
(Large Catechism, Part III, Sixth Petition)