I would not change my blest estate for all the world calls good or great.

The speaker contrasts spiritual contentment with worldly measures of success. “Blest estate” suggests a condition of inward blessedness—often, in Watts’s devotional idiom, the security of faith and the hope of salvation—set against what “the world calls good or great,” i.e., wealth, status, and public acclaim. The line implies that true well-being is not improved by external promotion; it is a settled happiness grounded in divine favor rather than social comparison. In keeping with Watts’s hymnody, the sentiment encourages readers to re-evaluate ambition and to prize gratitude and piety over the restless pursuit of reputation.