Early in his preaching ministry, Isaac Watts wrote out each sermon in manuscript, but he was careful not to confine himself too closely to his prepared text, "amplifying and altering as he found inclination or occasion, and that with the utmost freedom." Johnson describes Watts as he gained maturity as a preacher: "Such was his flow of thoughts, and such his promptitude of language, that in the latter part of his life he did not precompose his cursory sermons, but, having adjusted the heads and sketched out some particulars, trusted for success to his extemporary powers." Perhaps Watts found that by carefully studying the biblical text and by organizing its meaning in poetic verse in a hymn, the meaning of the text became so rooted in his understanding that he no longer needed to rely on a written sermon manuscript.
Watts' physical weakness disadvantaged him in his role as a pastor. So loved was he by his congregation in the pulpit that they longed for pastoral visits in their homes. Watts attempted to both preach and make regular pastoral visits:
To stated and public instruction he added familiar visits and personal application, and was careful to improve the opportunities which conversation offered of diffusing and increasing the influence of religion. By his natural temper he was quick of resentment; but by his established and habitual practice he was gentle, modest, and inoffensive. His tenderness appeared in his attention to children, and to the poor.
But his fragile health would not allow him to sustain the frequent visits that he desired to make to the homes of his congregants. Due to the limitations of his health, in July 1703, the now much larger congregation provided Watts with an assistant, Samuel Price, with whom Watts served in friendship and mutual respect for the remainder of his ministry.
Watts’ theology became their theology; his doxology became their doxology
These years of preparing sermons required Watts to dig deeply into the meaning of the inspired text. Preaching forced him to copiously cross-reference biblical themes, to compare Scripture with Scripture, to take deeply into his soul the sacred history, figurative language, imaginative comparisons, and doctrinal truths of the Bible. And he had to stand before his congregation, made up of rich and poor, high-born and common, elderly, middle-aged, newly married, and teenage, and even children and lisping toddlers. Few things could have prepared him to awaken the imagination of his hearers better than these years of close, precise biblical study and exposition.
Watts' hymns, not surprisingly, have been called rhymed sermons. Because they were undiluted theology conveyed to the mind and heart through Watts' poetic imagination and gifted wonder, his people—and all who sing Watts' hymns today—were dazzled with the splendor of Christ and the gospel. Through his hymns, his flock apprehended biblical truth with both mind and spirit. Watts' theology became their theology; his doxology became their doxology.