We sang an arrangement of the following hymn in church today:
God moves in a mysterious way
His wonders to perform;
He plants His footsteps in the sea
And rides upon the storm.
Deep in unfathomable mines
Of never failing skill
He treasures up His bright designs
And works His sovereign will.
Ye fearful saints, fresh courage take;
The clouds ye so much dread
Are big with mercy and shall break
In blessings on your head.
Judge not the Lord by feeble sense,
But trust Him for His grace;
Behind a frowning providence
He hides a smiling face.
His purposes will ripen fast,
Unfolding every hour;
The bud may have a bitter taste,
But sweet will be the flower.
Blind unbelief is sure to err
And scan His work in vain;
God is His own interpreter,
And He will make it plain.
"God Moves in a Mysterious Way" by William Cowper
The linked page cites John 13:7 as a key verse to consider along with the hymn. I would add John 16:19-22 as well. But, the passage that particularly comes to my mind is Matthew 15:21-28, which is the story of a foreign woman who had more faith than all of the Pharisees and Sadducees put together.
I love Martin Luther's sermon on the passage. Even though the whole sermon is gold, here are some excerpts to give a flavor of it:
3. But see in this example how Christ like a hunter exercises and chases faith in his followers in order that it may become strong and firm. First when the woman follows him upon hearing of his fame and cries with assured confidence that he would according to his reputation deal mercifully with her, Christ certainly acts differently, as if to let her faith and good confidence be in vain and turn his good reputation into a lie, so that she could have thought: Is this the gracious, friendly man? or: Are these the good words, that I have heard spoken about him, upon which I have depended? It must not be true; he is my enemy and will not receive me; nevertheless he might speak a word and tell me that he will have nothing to do with me. Now he is as silent as a stone. Behold, this is a very hard rebuff, when God appears so earnest and angry and conceals his grace so high and deep; as those know so well, who feel and experience it in their hearts. Therefore she imagines he will not fulfil what he has spoken, and will let his Word be false; as it happened to the children of Israel at the Red Sea and to many other saints... 10. All this, however, is written for our comfort and instruction, that we may know how deeply God conceals his grace before our face, and that we may not estimate him according to our feelings and thinking, but strictly according to his Word. For here you see, though Christ appears to be even hardhearted, yet he gives no final decision by saying "No." All his answers indeed sound like no, but they are not no, they remain undecided and pending. For he does not say: I will not hear thee; but is silent and passive, and says neither yes nor no. In like manner he does not say she is not of the house of Israel; but he is sent only to the house of Israel; he leaves it undecided and pending between yes and no. So he does not say, Thou art a dog, one should not give thee of the children's bread; but it is not meet to take the children's bread and cast it to the dogs; leaving it undecided whether she is a dog or not. Yet all those trials of her faith sounded more like no than yes; but there was more yea in them than nay; aye, there is only yes in them, but it is very deep and very concealed, while there appears to be nothing but no.
11. By this is set forth the condition of our heart in times of temptation; Christ here represents how it feels. It thinks there is nothing but no and yet that is not true. Therefore it must turn from this feeling and lay hold of and retain the deep spiritual yes under and above the no with a firm faith in God's Word, as this poor woman does, and say God is right in his judgment which he visits upon us; then we have triumphed and caught Christ in his own words. As for example when we feel in our conscience that God rebukes us as sinners and judges us unworthy of the kingdom of heaven, then we experience hell, and we think we are lost forever. Now whoever understands here the actions of this poor woman and catches God in his own judgment, and says: Lord, it is true, I am a sinner and not worthy of thy grace; but still thou hast promised sinners forgiveness, and thou art come not to call the righteous, but, as St. Paul says in I Tim 1, 15, "to save sinners." Behold, then must God according to his own judgment have mercy upon us...
1:18 As surely as God is faithful, our word to you has not been Yes and No.
1:19 For the Son of God, Jesus Christ, whom we preached among you, Silva'nus and Timothy and I, was not Yes and No; but in him it is always Yes.
1:20 For all the promises of God find their Yes in him. That is why we utter the Amen through him, to the glory of God.
1:21 But it is God who establishes us with you in Christ, and has commissioned us;
1:22 he has put his seal upon us and given us his Spirit in our hearts as a guarantee.