De Moor VII:36: The Subjective Uncertainty of Reprobation
Hence Reprobation is Objectively Certain, or Immutable; see above, § 13, 14: but Subjectively Uncertain: because, α. Grace is granted through effectual Calling at various Moments, Matthew 20:1, 3, 5, 6, the sense of which Parable concerning the Workers in the Lord’s Vineyard our AUTHOR explains of Saving Vocation granted to men at various moments of life, Exercitationibus Textualibus XXVI, Part VI, and hence disputes at length for the Salvation of those Repenting at a late hour but truly, especially against JACOBUS BERNARDUS, Tractatu de Resipiscentia Sera, book II, chapters I-IV. God calls some in the first hour, like Jeremiah, Jeremiah 1:5, and John the Baptist, Luke 1:15; others in the third, like Samuel, 1 Samuel 2:26; 3:4, 10, 19-21, and Josiah, 2 Chronicles 34:1-3; others in the sixth, like Paul, Acts 9; others in the ninth, like Manasseh, 2 Chronicles 33:12-19; others at the eleventh hour and end of life, like the Thief on the cross, Luke 23:40-43, from which example out AUTHOR also disputes at length in favor of Sincere Repentance as Saving, Exercitationibus Textualibus XXXV, Part VI: compare below, Chapter XXII, § 32. β. And it reaches even the hardest, 1 Timothy 1:15, 16; etc.
So that no Desperation is able to arise from our doctrine, except in those that are guilty of the Sin against the Holy Spirit, most justly to be tormented by this punishment even now, while otherwise there is no certain indication of Reprobation before death. Therefore, it is mere calumny, what Episcopius asserts with others: the effect or necessary consequence of Reprobation is eternal Desperation over the Grace of God; which TRIGLAND sets forth in Episcopius’ words, and refutes at length and with perfect success, Antapologia, chapter XIV, pages 227-229, showing, that the whole reasoning of Episcopius, 1. rests upon a false hypothesis, that one is able à priori to have a knowledge of his Reprobation; which is altogether impossible, and among the hidden things, the knowledge of which God has reserved for himself. 2. To which is added another calumny of our Adversaries, as if we taught Absolute Reprobation and Election equally, not only with respect to antecedent Conditions, but also with respect to consequent Means, in such a way that the Reprobate would be condemned, even if he repented and believed upon Christ; which is altogether false and foreign to our doctrine: see above, § 12, and 14, Objection 4; and also read carefully SPANHEIM, Decadum Theologicarum VIII, § 4, opera, tome 3, column 1246. With the sealed Book of Predestination left to God, it is fitting that we open the Book of the Law and Gospel, whence we are instructed concerning our appropriate duty and learn the way of perfect grace to God’s saving communion, being altogether certain of the infallible fulfillment of the promises set forth in the Gospel.
But a holy Solicitude only hence arises, to avoid the Judgment of God upon the Reprobates, and to confirm salvation: compare the Canons of Dort, chapter 1, article 16.
 See Deuteronomy 29:29.  Canons of Dort, chapter 1, article 16: “Those who do not yet experience a lively faith in Christ, an assured confidence of soul, peace of conscience, an earnest endeavor after filial obedience, and glorying in God through Christ, efficaciously wrought in them, and do nevertheless persist in the use of the means which God hath appointed for working these graces in us, ought not to be alarmed at the mention of reprobation, nor to rank themselves among the reprobate, but diligently to persevere in the use of means, and with ardent desires devoutly and humbly to wait for a season of richer grace. Much less cause have they to be terrified by the doctrine of reprobation, who, though they seriously desire to be turned to God, to please Him only, and to be delivered from the body of death, cannot yet reach that measure of holiness and faith to which they aspire; since a merciful God has promised that He will not quench the smoking flax nor break the bruised reed. But this doctrine is justly terrible to those, who, regardless of God and of the Savior Jesus Christ, have wholly given themselves up to the cares of the world and the pleasures of the flesh, so long as they are not seriously converted to God.”