Dictionary of National Biography, Vol. 17, p. 496 (1909 ed.):
He entered the university of Edinburgh in 1617, graduated in 1621, and in 1623 was appointed regent of humanity, having been recommended by the professors for 'his eminent abilities of mind and virtuous disposition.' The records of the two council of Edinburgh under 3 Feb. 1626 contain the following: 'Forasmuch as it being declared by the principal of the college that Mr. Samuel Rutherford, regent of humanity, has fallen in fornication with Eupham Hamilton, and has committed a great scandal in the college and...has since demitted his charge therein, therefore elects and nominates...commissioners...with power...to insist for depriving of the said Mr. Samuel, and being deprived for filling of the said place with a sufficient person.' Rutherford married the said Eupham, and his whole subsequent life was a reparation for the wrong he had done. According to his own statement, he had 'suffered the sun to be high in heaven' before he became seriously religious.
Joel R. Beeke & Randall J. Pederson, Meet the Puritans, p. 721, adds:
In 1623, Rutherford was chosen to serve as Professor of Humanity at Edinburgh, with responsibilities as a Latin tutor. Two years later, he was forced to resign after behaving inappropriately with a young woman named Euphame Hamilton, whom he subsequently married. God apparently used this incident to initiate or further his conversion. In a letter to Robert Stuart (1637), Rutherford wrote, “Ye have gotten a great advantage in the way of heaven, that ye have started to the gate in the morning. Like a fool, as I was, I suffered my sun to be high in the heaven, and near afternoon, before I ever took the gate by the end.”