My favorite love letter (besides the ones I write for Noël and she for me) is from the 19-year-old Jonathan Edwards to the girl he was falling in love with in the summer of 1723. On the front page of his Greek grammar he wrote the only kind of love song his heart was capable of. Take a deep breath.

They say there is a young lady in [New Haven] who is beloved of that great Being who made and rules the world, and that there are certain seasons in which this great Being, in some way or other invisible, comes to her and fills her mind with exceeding sweet delight, and that she hardly cares for anything, except to meditate on him—that she expects after a while to be received up where he is, to be raised up out of the world and caught up into heaven; being assured that he loves her too well to let her remain at a distance from him always. There she is to dwell with him, and to be ravished with his love and delight forever…. She has a strange sweetness in her mind, and singular purity in her affections; is most just and conscientious in all her conduct; and you could not persuade her to do anything wrong or sinful, if you would give her all the world, lest she should offend this great Being. She is of a wonderful sweetness, calmness and universal benevolence of mind; especially after this great God has manifested himself to her mind…. She loves to be alone, walking in the fields and groves, and seems to have someone invisible always conversing with her.

Sarah was thirteen years old at the time! Four years later they were married. In the next 23 years they had eleven children, eight daughters and three sons.

In case you can’t relate to Edwards’ Valentine, Martyn Lloyd-Jones is closer to earth. On September 25, 1939 when he was forty, the London pastor and latter-day Puritan wrote:

My dear Bethan,

Thank you for your letter of this morning, though I am very angry that you should have been up till 11:30 PM writing it! I see that you are quite incorrigible! The idea that I shall become used to being without you is really funny. I could speak for a long time on the subject. As I have told you many, many times, the passing of the years does nothing but deepen and intensify my love for you. When I think of those days in London in 1925 and ’26, when I thought that no greater love was possible, I could laugh.

But honestly, during this last year I had come to believe that it was not possible for a man to love his wife more than I loved you. And yet I see that there is no reason to live, and that it is still true that “absence makes the heart grow fonder.” I am quite certain that there is no lover, anywhere, writing to his girl who is quite as mad about her as I am. Indeed I pity those lovers who are not married. Well, I had better put a curb on things or I shall spend the night writing to you . . . .

Ever yours,
—Martyn

If you like these glimpses into the heart of Christian lovers I recommend Michael A. G. Haykin, with Victoria J. Haykin, The Christian Lover: The Sweetness of Love and Marriage in the Letters of Believers.