Benjamin West, the Pennsylvania artist who became history painter to King George III and was a founder of the Royal Academy of Arts, London, ranks among the most important painters of the eighteenth century. West scholars have confirmed the attribution of this drawing to West, although they disagree on the subject of the work. The subject of this drawing most likely derives from the biblical story related in Acts, chapters 15–18, in which Paul blesses the converted Onesimus (shown with his arms crossed as if receiving a blessing), a runaway slave and fellow prisoner with his master Epaphras (who draws back in astonishment at the event). As the converted Onesimus was thought to be the later bishop of Ephesus, who gathered together the epistles of Saint Paul, this story was considered significant and formed a part of the fourth dispensation, the last epoch of Christian salvation. 

This may be a preparatory study for the mural commission on the subject of revealed religion that West received in 1780 from King George III for a new royal chapel at Windsor. The painting for this subject may never have been realized. Only twenty-eight of the thirty-five intended works were finished before the king canceled the project. An alternative is that this sketch is a study for an altar window based on the Conversion of Saint Paul in Birmingham, another commission that West received from the king. 

Book excerpt: David B. Warren, Michael K. Brown, Elizabeth Ann Coleman, and Emily Ballew Neff. American Decorative Arts and Paintings in the Bayou Bend Collection. Houston: Princeton Univ. Press, 1998.