Wilhelmus van Irhoven (1698-1760), also known as Willem van Irhoven, was a Voetian professor of theology and church history at the University of Utrecht from 1737 until his death. Prior to taking up his position at Utrecht, he spent fifteen years as a Dutch Reformed pastor not far from Utrecht, in the town of Ede, Gelderland, from 1722 to 1737. During his pastorate, he wrote a large work dedicated entirely to the doctrine of assurance, titled Gronden van het Verzekerd Christendom (first edition 1730). The title translates as Grounds of Assured Christianity and, to give you an idea of its size, the third edition of this work (1744), from which I translated the excerpt below, is over 700 pages long. The work is a collection of lectures in question and answer format, loaded throughout with biblical references, which Van Irhoven presented to congregants on various occasions and which he called winteroefeningen (winter exercitations).
After having discussed adoption, regeneration, faith, and conversion in the first four chapters, Van Irhoven turns to a discussion of assurance in chapter 5. He starts the chapter by arguing that, in order to enjoy the assurance of being in a state of grace (that is, being saved in Christ), you have to know and be conscious of whether you are truly born again, whether you truly believe, and whether you have truly been converted. These things may be ascertained by the Word of God, by your conscience, and by the testimony of the Holy Spirit. Moreover, whether you are in a state of grace may be tested by your deeds which are wrought by faith, as well as by your sensitivity to and brokenness over sin.
Below is an excerpt from later in the chapter.
Q. Can it be properly and clearly deduced from God’s Word that one can be assured of one’s adoption as a child of God?
A. Yes, see Is. 63:16. You, O LORD, are our Father, our Redeemer from of old is your name. Gal. 4:6. And because you are sons, God has sent the Spirit of his Son into our hearts, crying, ‘Abba! Father!’ See also Rom. 8:29, 30…
Q. How is one assured of one’s adoption as a child of God from the consciousness of one’s good inward state?
A. By the fruit of faith. But to all who did receive him, who believed in his name, he gave the right to become children of God. Jn. 1:12.
Q. Can one be assured of one’s election?
A. Yes. See 1 Thess. 1:4. For we know, beloved brothers, your election of God. And 1 Thess. 5:6. For God has not destined us for wrath, but to obtain salvation through our Lord Jesus Christ. See furthermore 2 Pet. 1:10. Therefore, brothers, be all the more diligent to make your calling and election sure, for if you practice these things you will never fall. Lk. 10:20. Nevertheless, do not rejoice in this, that the spirits are subject to you, but rejoice that your names are written in heaven. And so forth.
Q. How are you assured of your election?
A. By considering that faith and conversion are the fruits and effects of election. Acts 13:48. And as many as were appointed to eternal life believed. Rom. 8:30. And those whom he predestined he also called, and those whom he called he also justified, and those whom he justified he also glorified.
Q. Can one also be assured of the love of God and Christ towards us, that our service is pleasing to them, that they will hear our prayers, and so forth?
A. Yes. 1 Jn. 4:16. So we have come to know and to believe the love that God has for us. 2 Thess. 2:16. Our Lord Jesus Christ himself, and God our Father, who loved us and gave us eternal comfort and good hope through grace. Song 7:10. I am my beloved’s, and his desire is for me. Our religion is a pleasing sacrifice to God, Rom. 12:1. Our charity towards our fellow men is a fragrant smell and an acceptable sacrifice, pleasing to God. Phil. 4:18. And regarding our prayers, see 1 Jn. 5:14, 15. And this is the confidence that we have toward him, that if we ask anything according to his will he hears us. And if we know that he hears us in whatever we ask, we know that we have the requests that we have asked of him.
Q. How is one assured of the love of God the Father and of Christ towards us, that our service is thus pleasing to them?
A. By considering the ground and cause of our adoption as children. 1 Jn. 3:1. See what kind of love the Father has given to us, that we should be called children of God. Jn. 3:16. For God so loved the world, that he gave his only Son, that whoever believes in him should not perish but have eternal life. Likewise, also from the fruits of faith and conversion. Jn. 14:21, 23. Whoever has my commandments and keeps them, he it is who loves me. And he who loves me will be loved by my Father, and I will love him.
Q. Can one also be assured that our sins are forgiven and will moreover be daily forgiven?
A. Yes. Ps. 103:3. Who forgives all your iniquity, who heals all your diseases. Prov. 28:13. He who confesses and forsakes his sins will obtain mercy. Matt. 6:14. For if you forgive others their trespasses, your heavenly Father will also forgive you.
Q. How are you assured of the forgiveness of your sins?
A. By the fruit of faith. Acts 10:43. To him all the prophets bear witness that everyone who believes in him receives forgiveness of sins through his name.
Q. Can one also be assured that God will safeguard us, so that one will always remain in the state of grace?
A. Yes. 2 Tim. 4:18. The Lord will rescue me from every evil deed and bring me safely into his heavenly kingdom.
Q. How are you assured of your safeguarding?
A. Again by considering the fruit and the result of faith and conversion. Jn. 10:27, 28. My sheep will never perish, and no one will snatch them out of my hand. Prov. 24:16. For the righteous falls seven times and rises again. Ps. 37:24. Though he fall, he shall not be cast headlong, for the LORD upholds his hand. 1 Pet. 1:5. Who by God’s power are being guarded through faith for a salvation ready to be revealed in the last time.
Q. Can one also be assured of his future salvation?
A. Yes. Ps. 17:15. I shall behold your face in righteousness; when I awake, I shall be satisfied with your likeness. 2 Cor. 5:1. For we know that if the tent, which is our earthly home, is destroyed, we have a building from God, a house not made with hands, eternal in the heavens.
Q. How are you assured of your salvation?
A. In the same way, by the result of faith. Jn. 3:36. Whoever believes in the Son has eternal life.
Van Irhoven goes on to argue that although some Christian have doubts about their salvation at various stages in their lives, yet an habitual working faith (that is, true faith which produces good works) together with the paternal goodness of God by which He assures his children of their adoption, would bear witness to one’s conscience that one is indeed saved. Furthermore, this assurance of salvation does not remove the fear of God in a believer, nor does it allow the believer to live in carnal carelessness, but rather provides the believer with all the more reason to fear God and obey his commandments.