The Doctrine of Justification by Faith

2. Imputation may justly ensue, ex voluntaria sponsione; when one freely and willingly undertakes to answer for another. An illustrious instance hereof we have in that ⟨p. 238⟩passage of the Apostle unto Philemon, in the behalf of Onesimus; ver. 18. If he have wronged thee, or oweth thee ought, [Greek or Hebrew], impute it unto me, put it on my account. He supposeth that Philemon might have a double Action against Onesimus. (1) Injuriarum, of wrongs; [Greek or Hebrew], if he hath dealt unjustly with thee or by thee, if he hath so wronged thee as to render himself obnoxious unto punishment; (2) Damni, or of loss; [Greek or Hebrew], if he oweth thee ought, be a debtor unto thee, which made him liable to payment or restitution. In this state the Apostle interposeth himself by a voluntary sponsion, to undertake for Onesimus. I Paul have written it with my own hand [Greek or Hebrew] I Paul will answer for the whole. And this he did by the Transcription of both the debts of Onesimus unto himself; For the crime was of that nature as might be taken away by compurgation, being not Capital. And the Imputation of them unto him, was made just by his voluntary undertaking of them. Account me, saith he, the Person that hath done these things; and I will make satisfaction, so that nothing be charged on Onesimus. So Judah voluntarily undertook unto Jacob, for the safety of Benjamin, and obliged himself unto perpetual Guilt in case of failure; Gen. 43.9. I will be surety for him, of my hand shalt thou require him, if I bring him not unto thee, and set him before thee, [Greek or Hebrew] I will sin, or be a sinner before thee always; be guilty and as we say, bear the blame. So he expresseth himself again unto Joseph, Chap. 44.32. It seems this is the nature and office of a Surety; what he undertaketh for, is justly to be required at his hand, as if he had been originally and personally concerned in it. And this voluntary sponsion was one ground of the Imputation of our sin unto Christ. He took on him the person of the whole Church that had sinned, to answer for what they had done against God and the Law. Hence that Imputation was fundamentaliter ex compacto, ex voluntaria sponsione, ⟨p. 239⟩it had its foundation in his voluntary undertaking. But on supposition hereof;