II. The second observable circumstance in the inspired account of Lydia's conversion is, _its accomplishment by divine agency_. It is stated that the LORD opened her heart. The effect is not ascribed to the apostle Paul, or his illustrious coadjutors in the Christian ministry. They might speak with the tongue of angels, and hum with the zeal of seraphs; to them might be given in trust "the everlasting Gospel," which, like the apocalyptic angel, they were carrying through "the midst of heaven" to the inhabitants of the earth, "to every nation, and kindred, and tongue, and people;" they might indeed possess the power not only of placing facts in the clearest light, or urging arguments in the most forcible manner, but even of working miracles; still they could not "open the heart." Indefatigable as they were in their labours, they could not command success. At this precise point human instrumentality ceases, and divine agency commences. It is by no means an unfrequent effect of ministerial fidelity, to confirm the native aversion of the impenitent to the doctrines of Christ. Pride resists conviction, and fosters prejudice; and however unanswerable the statements, or fervent the appeals which may be addressed to them, the mind still remains unsubdued, the heart is still unopened. It requires the interposal of a mightier power than either reason, remonstrance, or miracle, to accomplish this wonderful transformation of character. Hosts of apostles and legions of angels would be incompetent by their own unaided exertions, to do "any thing as of themselves;" to give light to _one_ blind eye, or to rectify _one_ prejudiced heart.