For those on the One-Year Lectionary, and who have not observed the Michaelmas skip, the Gospel for this Sunday is John 4:46—54, the healing of the nobleman’s son.

Here’s a little help from Luther’s Church Postil:

Today’s Gospel pictures to us a remarkable example of faith, for St. John carefully notes at three different times that the nobleman believed, and we may indeed be greatly moved by the fact, and ask, what kind of faith must he have had, the the Evangelist mentioned it so often. . . . 

In the first place, I have often said that faith through the Gospel fully brings the Lord Jesus with all his riches home to every man; and that one Christian has just as much [of the Lord and His riches] as another, and the child baptized today has not less than St. Peter and all the saints in heaven. We are all equal and alike in reference to faith [with regard to heavenly treasures], and one person has his treasure just as full and complete as another.

Our Gospel lesson speaks further of the increase of faith, and here there is a difference. Although faith fully possesses Christ and all his riches, yet it must nevertheless be continually kept in motion and exercised, so that it may have assurance, and firmly retain its treasures. There is a difference between having a thing and firmly keeping hold of it, between a strong and a weak faith. Such a great treasure should be firmly seized and well guarded, so that it may not be easily lost or taken from us. I may have it indeed in its entirety, although I hold it only in a paper sack, but it is not so well preserved as if I had it locked in an iron chest.

Therefore we must so live on the earth, not that we think of something different that is better to acquire than what we already possess; but that we strive to lay hold of the treasure more and more firmly and securely from day to day. We have no reason to seek anything more than faith; but here we must see to it how faith may grow and become stronger. Thus we read in the Gospel, that, although the disciples of Christ without doubt believed (for otherwise they had not followed him), yet he often rebuked them on account of their weak faith. They had indeed faith, but when it was put to the test, they let it sink and did not support it. So it is with all Christians; where faith is not continually kept in motion and exercised, it weakens and decreases, so that it must indeed vanish; and yet we do not see nor feel this weakness ourselves, except in times of need and temptation, when unbelief rages too strongly; and yet for that very reason faith must have temptations in which it may battle and grow. . . . 

Therefore you should not imagine it is enough if you have commenced to believe; but you must diligently watch that your faith continue firm, or it will vanish; you are to see how you may retain this treasure you have embraced; for satan concentrates all his skill and strength on how to tear it out of your heart. Therefore growth of your faith is truly as necessary as its beginning, and indeed more so; but all is the work of God. The young milk-faith is sweet and weak; but when long marches are required and faith is attacked, then God must strengthen it, or it will not hold the field of battle. . . . 

“Except ye see signs and wonders, ye will no wise believe.” With these words [Jesus] gives faith a scornful rebuff that it cannot stand. The poor man was terrified and his faith at once began to sink and to vanish, therefore he says: “Sir, come down ere my child die.” . . . and [Jesus] speaks thus to the father: “Go thy way; thy son liveth.” 

Had he thus said to him before that his son would live he would have been unable to believe; but now he believes when faith springs forth in his heart and begets in him another faith, so that he becomes a different man. Therefore the Lord adds to his great rebuke great strength. For, he must now cling to that which he does not see; for he did not before believe that Christ had such power and influence that he could heal his son when he did not see him and was not present with him. It is truly strong faith, that a heart can believe what it does not see and understand, contrary to all the senses and reason, and can cling only to God’s Word. . . . In faith one must look to nothing but the Word of God. . . .