I do not at this moment remember any striking English poem illustrating this fact; but there is a pretty little poem in French by Victor Hugo showing well the relation between successful love and religious feeling in simple minds.

Here is an English translation of it.
The subject is simply a walk at night, the girl-bride leaning upon the arm of her husband; and his memory of the evening is thus expressed: The trembling arm I pressed Fondly; our thoughts confessed Love's conquest tender; God filled the vast sweet night, Love filled our hearts; the light Of stars made splendour.
Even as we walked and dreamed, 'Twixt heaven and earth, it seemed Our souls were speaking; The stars looked on thy face; Thine eyes through violet space The stars were seeking.
And from the astral light Feeling the soft sweet night Thrill to thy soul, Thou saidst: "O God of Bliss, Lord of the Blue Abyss, Thou madest the whole!" And the stars whispered low To the God of Space, "We know, God of Eternity, Dear Lord, all Love is Thine, Even by Love's Light we shine! Thou madest Beauty!" Of course here the religious feeling itself is part of the illusion, but it serves to give great depth and beauty to simple feeling.

Besides, the poem illustrates one truth very forcibly--namely, that when we are perfectly happy all the universe appears to be divine and divinely beautiful; in other words, we are in heaven.

On the contrary, when we are very unhappy the universe appears to be a kind of hell, in which there is no hope, no joy, and no gods to pray to.
But the special reason I wished to call attention to Victor Hugo's lyric is that it has that particular quality called by philosophical critics "cosmic emotion." Cosmic emotion means the highest quality of human emotion.

The word "cosmos" signifies the universe--not simply this world, but all the hundred millions of suns and worlds in the known heaven.