As it is written, “Jacob I loved, but Esau I hated.”
What shall we say then? Is there injustice on God's part?
By no means! For he says to Moses, “I will have mercy
on whom I have mercy, and I will have compassion on whom I have compassion.”
So then it depends not on human will or exertion, but on God, who has mercy. For the Scripture says to Pharaoh, “For this very purpose I have raised you up,
that I might show My power in you, and that My name might be proclaimed
in all the earth.” So then he has mercy on whomever he wills,
and he hardens whomever he wills.
You will say to me then, “Why does he still find fault?
For who can resist his will?” But who are you, O man, to answer back to God?
Will what is molded say to its molder, “Why have you made me like this?”
Has the potter no right over the clay, to make out of the same lump
one vessel for honorable use and another for dishonorable use?
What if God, desiring to show his wrath and to make known his power,
has endured with much patience vessels of wrath prepared for destruction,
in order to make known the riches of his glory for vessels of mercy,
which he has prepared beforehand for glory—
Reprobation is the antithesis to election and necessarily follows from it. If God does not elect a person, He rejects him. If God decides not to convert a sinner into a saint, He decides to let him remain a sinner (1). If God decides not to work in a man to will and to do according to God's will, He decides to leave the man to will and to do according to his own will. When God effectually operates upon the human will, it is election. When God does not effectually operate upon the human will, it is reprobation. Election is the expression of divine mercy; reprobation of divine justice. Paul teaches this in Romans 11:22, "Behold the goodness and severity of God (divine compassion and divine justice) on them which fell severity; but toward you goodness."
Reprobation relates to regenerating grace, not common grace. It is an error to suppose that the reprobate are entirely destitute of grace. All mankind enjoys common grace. There are no elect or reprobate in this refernece. Every human being experiences some degree of the ordinary influences of the Spirit of God. St. Paul teaches that God strives with man universally. He convicts him of sin and urges him to repent of it and forsake it (Roms. 1:19-20; 2:3-4; Acts 17:24-31).
Reprobation comprises preterition and condemnation of damnation. Preterition is a sovereign act; condemnation is a judicial act. God passes by or omits an individual in the bestowment of regenerating grace because of His sovereign good pleasure (eudokia). The reason of condemnation is known: sin is the reason. The reason for preterition is unknown: it is not sin, because the elect are as sinful as the nonelect. In preterition, God’s action is permissive; inaction rather than action. In condemnation God’s action is efficient and positive.
Preterition is “letting things stand” as they are. To omit or pretermit is to leave or let alone. The idea is found in Luke 17:34, “The one shall be taken, the other shall be left…”
Preterition in the bestowment of regenerating grace is plainly taught in Scripture (Isaiah 6:9-10*; Matt. 11:25-26; 13:11; 22:14; Luke 17:34; John 10:26; 12:39; Acts 1:16; 2 Thess. 2:11-12; 2 Tim. 2:20; 1 Peter 2:8; Rom. 9:17-22; Jude 1:4).
*Isaiah 6:9-10 is quoted more in the N.T. than any other O.T. text (4x’s in the gospels; 1x in Acts; and 1x in Romans). He said, "Go, and tell this people: 'Keep on listening, but do not perceive; Keep on looking, but do not understand.' "Render the hearts of this people insensitive, their ears dull, and their eyes dim, otherwise they might see with their eyes, hear with their ears, understand with their hearts, and return and be healed."
Source: William G.T. Shedd - "Dogmatic Theology"-third edition; P&R Publishing, 2003 - p. 333-336
1. Shedd is not implying here that Christians are not any longer sinners. He is using the term to describe nature (unregenerate, sinner; regenerate, saint.) Saints are still sinners (Prov. 24:9) saved by grace through faith in Jesus Christ (Eph. 4-6). Our old nature has been crucified with Christ (Gal. 2:20-21; 2 Cor. 5:17). Though we have been completely delivered from the penalty of sin (salvation), we have not been delivered from the presence of sin (glorification) nor entirely from the practice of sin (sanctification) (Titus 2:12) until we are home with the Lord (Roms. 8:29-31; Titus 2:13). None of us have arrived to the fulness of our sanctification in this life... have we? (Eph. 5:23-27; Rom. 12:1-2). We all still struggle with sin and its desires (Rom. 7:7-10).
But, as new creations in Christ, a genuine Christian will not be given over to the constant "practice of sin" without any repentance or conviction of conscience (Gal. 5:16ff). We will ultimately desire to please the Lord by turning from those things which do not honor Him and then doing the things that do bring Him glory and delight. This is a constant struggle that all of us face - even the Apostle Paul faced it daily in his own life (Rom. 7:14-20). But when we do sin, our hope is that we have an adovate with the Father, Jesus Christ the righteous who intercedes for us (1 John 2:1-2). We are still sinners, that by God's grace are now made saints--His brethren (Heb. 2:11). We are new creatures, but incarcerated in unredeemed flesh (Rom. 8:23) and that is the source of the battle that rages within each day as we daily walk in the Lord (Col. 3:1-14).
BUT, there is "no condemnation for those who are in Christ Jesus the Lord" (Rom. 8:1). I hope this helps clarify the distinction of what I believe Shedd is saying.