The production of sin is based on ability and opportunity. Before their fall into sin, Adam and Eve had the capacity and opportunity either to obey or disobey God. Even before they had a sin nature, Adam and Eve could manufacture sin from the source of their own volition. Adam and Eve’s abilities are described by the Latin phrases posse peccare (able to sin), and posse non peccare (able not to sin). They truly had free choice to obey God or Satan. Free choice also belonged to Lucifer at his own fall, when he turned away from God through self-corruption, and enticed a third of the angels to sin with him (Isa. 14:12-14; Ezek. 28:12-18; Rev. 12:4, 9). The Christian, who has God’s word and is indwelt by the Holy Spirit, also has the ability to obey God and resist both external and internal temptation (Rom. 6:11; Col. 3:5). The Christian does not have to sin, but chooses to do so by an act of his will when he yields to temptation. Jesus’ temptations were external (just like Adam and Eve’s), whereas all humanity after the fall, both saved and unsaved, encounter temptations both external (from other fallen creatures, both angelic and human) and internal (the sin nature).
The unbeliever, who is devoid of the Holy Spirit, cannot be obedient to God. This inability is described by the Latin phrase non posse non peccare (not able not to sin, or positively stated able only to sin). The unbeliever has neither the Holy Spirit nor God’s word, and therefore is perpetually governed by his sinful nature and the satanically-controlled world in which he lives. The unbeliever can be moral or immoral, religious or irreligious, but he can only produce sin because he resides in a state of spiritual death.
God cannot sin (Hab. 1:13; Tit. 1:2; Heb. 6:18). This truth is described by the Latin phrase non posse peccare (not able to sin). Because God is perfect righteousness, He cannot act contrary to His own holy nature; therefore, He can never manufacture sin. This is true of Jesus right now in heaven where there is no more temptation, and this is also be true of a believer who enters into heaven at death, the rapture, or after history has closed. So then, the Latin phrases are:
- posse peccare (able to sin)
- posse non peccare (able not to sin)
- non posse non peccare (not able not to sin, or positively stated able only to sin)
- non posse peccare (not able to sin)
“Could not” or “would not” sin?
A question that has troubled theologians for many years is whether Jesus, during His time on earth, could have sinned? The Bible teaches that Jesus is undiminished deity combined together forever with true humanity into one Person, which in theology is called the hypostatic union. At a point in time, God the Son took upon Himself true humanity and walked on the earth. He lived a sinless life and died a substitutionary death for all mankind (1 Cor. 15:3-4; John 6:69; 9:16; Rom. 8:3; 2 Cor. 5:21; Heb. 4:15; 7:26; 1 Peter 2:22; 3:18; 1 John 3:5). Regarding the union of Jesus’ two natures, Joseph Sahl states:
In the Incarnation the eternal Son of God was inseparably united to an unfallen human nature. Thus He is unique from all other men not only in that He was kept from the consequences of Adam’s sin in His perfect humanity but also in that He was the God-Man. In this way one Person, the Lord Jesus Christ, possessed a divine nature as well as a human nature. Though the divine nature of Christ had eternal existence apart from the humanity of Jesus Christ (Heb 10:5), that was not true of His human nature. His humanity exists only in union with His deity. Thus the personality expressed in the humanity of Jesus Christ was nothing less than that personality of God the Son, the Eternal Word who became flesh.
R. B. Thieme Jr. argues that in His humanity Jesus was peccable (able to sin). He believes that as God, Jesus was non posse peccare (not able to sin), but as a human, He was posse non peccare (able not to sin) because He continually relied on Scripture and the Holy Spirit to resist external temptations. In short, he believes that as God, Jesus could not sin, but as a human, He would not sin. In his book, The Integrity of God, he states:
Remember that Christ in His humanity could be tempted and could have sinned. In His deity, however, neither could He be tempted nor could He commit sin. If you add up these characteristics, the God-Man in hypostatic union was temptable but impeccable. In other words, through His human volition He was able to avoid sin when He was tempted as a man; in His divine essence, the integrity of God meant sin was completely out of the question.
Lewis Sperry Chafer argues that the humanity of Christ was impeccable (could not sin). The argument by Chafer is that God the Son took upon Himself humanity, and that what happened with regard to His human nature, happened to His divine nature as well. For Chafer, to say that Jesus could sin, is to say that God can sin, and that’s an impossible act. Chafer argues:
Since this bond of union which unites Christ’s two natures—for He is one person—is so complete, the humanity of Christ could not sin. Should His humanity sin, God would sin. When the absolute deity of Christ is recognized, there is no logic which is more inexorable than this. Though unsupported unfallen humanity might sin, a theanthropic Person even if He incorporates an unfallen human nature is incapable of sinning. The contention that could, but would not, sin is far removed from the contention that Christ could not sin. The former either denies His deity or else dishonors God with the calumnious averment that God is Himself capable of sinning. Again, it must be declared that Christ’s human traits which did not involve moral issues could be exhibited freely. The idea might be admitted with certain reservations that He was both omnipotent and impotent, omniscient and ignorant, infinite and finite, unlimited and limited; but it could never be allowed that He was both peccable and impeccable.
The Bible teaches that Jesus faced real temptations (Matt. 4:11), and whether one believes that He could not sin, or would not sin, it clearly teaches that He did not sin (Heb. 4:15). Jesus did not manufacture any personal sin for which He needed to atone, for if He had sinned, He would have disqualified Himself from going to the cross as an atoning sacrifice for others. Jesus died on the cross, bearing the sin of the world, dying in the place of sinners (John 3:16; Rom. 5:6-8).
Did Jesus have one will or two wills?
Another matter related to this subject is whether Jesus had one will or two wills. Jesus is both God and man, existing as one person with two natures. Some argue that since Jesus has two natures, He therefore has two wills. However, others argue that Jesus—though having two natures—is one Person, and therefore has one will. If will belongs to nature, then Jesus has two, but if will belongs to personhood, then Jesus has one. In favor of the one-will view, John F. Walvoord writes:
In view of the complete divine and human natures in Christ, the question has been raised whether each nature had its corresponding will. If by will is meant desire, it is clear that there could be conflicting desires in the divine and human natures of Christ. If by will, however, is meant that resulting moral decision, one person can have only one will. In the case of Christ, this will was always the will of God. Hence, when Christ prayed in the garden of Gethsemane: “My Father, if it be possible, let this cup pass from me: nevertheless, not as I will, but as thou wilt” (Matt 26:39), here, as in all other cases, the ultimate sovereign will of Christ was to do the Father’s will. It was natural to the human nature to desire to avoid the cross even as it was in keeping with the divine nature to avoid the contact with sin involved in substitution. The will of God, however, was that Christ should die, and this Christ willingly did. It is therefore no more proper to speak of two wills in Christ than it is of two wills in an ordinary believer who has both a sin nature and a new nature. A conflict of desires should not be equated with a conflict of moral choice.
Joseph Sahl also believes Jesus had only one will:
Though Christ was of both human and divine desires, He had only one determinative will. That determinative will is in the eternal Logos and continuously follows the will of the Father. Therefore statements one may make about what the humanity of Christ could or could not do must always be tempered by this understanding of the theanthropic Person.
Charles C. Ryrie disagrees with Walvoord & Sahl and argues that Christ had two wills, one for each nature. Ryrie states:
Did Christ have one or two wills? Chalcedon said one Christ in two natures united in one Person, implying two wills. In the seventh century the Monothelites insisted that Christ had but one will, but this view was declared heresy by the Council at Constantinople in 680. If will is defined as a “behavior complex” as Bushwell does, then our Lord may be said to have had a divine behavior pattern and a perfect human one as well; hence two wills. If will is defined as the resulting moral decision as Walvoord does, then the person of Christ always made only one moral decision; hence one will. However, it seems to me that every single decision stemmed from either the “will” of His divine nature or the “will” of His human nature or a blending of both, making it proper to think of two “wills.”
Lewis S. Chafer also believes Jesus had two wills:
What can be said, further, of the matter of will with regard to the theanthropic Person? Did He have one or two wills? The answer given to the Monothelites has never had to be changed. In order to be truly God, Christ had to have and did have, a divine will; similarly, to be really man, He had to have, and did have, a human will. Both wills worked harmoniously in obedience to the pleasure of the Father, the human will ever in subjection and following the divine.
The question of whether Jesus has one will or two perplexes even some of the best theologians. If volition is a part of the human and divine nature, then Christ has two wills because He has two natures (Ryrie & Chafer). However, if volition is a part of personhood, then Christ has one will because He is only one Person (Walvoord & Sahl).
Biblically, Jesus is fully God and fully man, existing as one Person with two natures, fully divine and fully human, without any diminishment or mixture of those two natures so as to reduce or pollute them. Whether Jesus has one will or two wills as some theologians argue, He was always compliant with the will of the Father, and this has resulted in our so great salvation.
Steven R. Cook, M. Div.
Joseph G. Sahl, “The Impeccability of Jesus Christ”, Bibliotheca Sacra (Vol. 140, 1983), 16.
 R. B. Thieme Jr., The Integrity of God (Houston, Texas, R. B. Thieme Jr. Bible Ministries,1998), 67-68.
 Lewis Sperry Chafer, Systematic Theology, 8 Volumes (Grand Rapids, Mich., Kregel Publications, 1993), 78.
John F. Walvoord, “The Incarnation of Christ–Part III: The Person of the Incarnate Christ” Bibliotheca Sacra 117 (1960): 201.
Joseph G. Sahl, “The Impeccability of Jesus Christ”, Bibliotheca Sacra (Vol. 140, 1983), 16.
 Charles C. Ryrie, Basic Theology (Wheaton, Ill., Victor Books, 1986), 251.
Lewis Sperry Chafer, “The Doctrine of Sin Part 4” Bibliotheca Sacra 92 (1935): 423.