Isaac Watts was the son of a schoolmaster, and was born in Southampton, July 17, 1674. He is said to have shown remarkable precocity in childhood, beginning the study of Latin, in his fourth year, and writing respectable verses at the age of seven. At the age of sixteen, he went to London to study in the Academy of the Rev. Thomas Rowe, an Independent minister. In 1698, he became assistant minister of the Independent Church, Berry St., London. In 1702, he became pastor. In 1712, he accepted an invitation to visit Sir Thomas Abney, at his residence of Abney Park, and at Sir Thomas' pressing request, made it his home for the remainder of his life. It was a residence most favourable for his health, and for the prosecution of his literary… Go to person page >
'Tis pure delight without alloy. J. Watts. [Divine Love Desired.] Published in his Horae Lyricae, 1706, Bk. i., in 6 stanzas of 4 lines and headed, "Ascending to Him in Heaven." In the American Methodist Episcopal Hymns, 1849, and in their Hymnal, 1878, it is given with the omission of stanza iv. as, "O 'tis delight without alloy." It is from the original, as above, that Watts took a portion for his hymn, "Happy the heart where graces reign."
--John Julian, Dictionary of Hymnology (1907)