IGNORANCE. In some instances, ignorance in Biblical usage denotes merely an innocent lack of information (Acts 23:5; 2 Cor 1:8). In its distinctively Biblical meaning, it is a specifically religious rather than an intellectual concept. Ignorance is a quality, not of the academically unschooled, but of the sinner. It is a result of sin and refers to that lack of religious knowledge man should, and would have, were he not a sinner. Thus ignorance no more indicates an intellectual state of poverty, than wisdom is a state of intellectual fullness. Ignorance is the lack of that religious knowledge which, possessed and practiced, is what the Bible calls wisdom. To know religious truth is knowledge; to practice religious truth is wisdom; to know truth and not to practice it is folly, the mark of the fool. Not to know religious truth and, consequently, to live in untruth, is ignorance.
Ignorance is a consequence of sin, for sin darkens the mind, depriving it of true knowledge of God and the self. Ignorance is, therefore, also a matrix of sin. Men sin in ignorance because of ignorance. Thus Paul says about the “princes of this world” who crucified Christ that they knew not the “wisdom of God,” “for had they known it, they would not have crucified the Lord of glory (1 Cor 2:8 KJV). Christians, non-Christians, and even the Church itself, sin because of ignorance. Yet, since ignorance is the consequence of man’s sin, sins done in ignorance are sinful and the doer of such sins is culpable.
Nonetheless, sins done in ignorance are less sinful and incur less guilt than sins done in full knowledge of their sinful character and which, accordingly, incur greater guilt. Thus Pilate’s guilt for the crucifixion of Christ is less than that of the Jews (John 19:11); but even the Jews were not fully conscious of the nature of their act and Jesus, therefore, invoked their forgiveness, “Father, forgive them, for they know not what they do” (Luke 23:34 KJV). The same lesser guilt and greater forgiveability of sins done in ignorance appears in Paul’s admission that he was a blasphemer and a persecutor of the Church, and indeed the chief of sinners (1 Tim 1:15 KJV) but that he obtained mercy because “I did it ignorantly in unbelief” (1:13 KJV). Paul speaks in a similar vein on Mars Hill when he declared that God “overlooked” (“winked at”) the “times of ignorance” during which men likened God to an idol made of stone and worshiped the idol (Acts 17:30). God in His mercy acts with forbearance on sins done in ignorance by pagans today and in all centuries past; there is a mercy of God greater than all man’s sins. Hence Paul’s prayer for Israel—who had a zeal that was not according to knowledge, for “being ignorant of God’s righteousness” they sought “to establish their own” (Rom 10:3 KJV)—is that “they may be saved” (10:1).
There is, however, a willful ignorance of God’s truth. There is a knowledge of God given in the things that are made that paganism sinfully suppressed (1:18), exchanged for a lie (v. 25), and were therefore without excuse (v. 20) and were accordingly punished (vv. 24-32). Yet even such sins of willful ignorance of the truth given in general revelation incur less culpability than sins of willful ignorance against the economy of special revelation; the former shall perish without law but the latter shall be judged by the law. Sins done either in ignorance, or willfully against the knowledge of God given to all men in the general revelation “that enlightens every man” (John 1:9) can be overlooked by God and can also be followed by repentance and forgiveness (which is more than being overlooked). That willful ignorance, which is the consequence of a conscious rejection of the knowledge of the truth revealed in Christ and made known in the Gospel proclamation, God will not overlook but subject to a divine judgment and fire that will devour the enemies of Christ (Heb 10:26f.). In self-conscious and knowledgeable rejection of Christ in His disclosure in Gospel proclamation, the sin of willful ignorance excludes man from that forgiving mercy of God that can forgive all other sins of ignorance.
International Standard Bible Encyclopedia (1915)