Monergism

Unwarranted confidence in human ability is a product of fallen human nature. This false confidence now fills the evangelical world; from the self-esteem gospel, to the health and wealth gospel, from those who have transformed the gospel into a product to be sold and sinners into consumers who want to buy, to others who treat Christian faith as being true simply because it works. This silences the doctrine of justification regardless of the official commitments of our churches.God's grace in Christ is not merely necessary but is the sole efficient cause of salvation. We confess that human beings are born spiritually dead and are incapable even of cooperating with regenerating grace. We reaffirm that in salvation we are rescued from God's wrath by his grace alone. It is the supernatural work of the Holy Spirit that brings us to Christ by releasing us from our bondage to sin and raising us from spiritual death to spiritual life. We deny that salvation is in any sense a human work. Human methods, techniques or strategies by themselves cannot accomplish this transformation. Faith is not produced by our unregenerated human nature.
The Cambridge Declaration

Luther recovered the gospel, and thereby instituted a truly evangelical revival, when he broke free from the Medieval-Scholastic Nature/Grace metaphysical scheme. In his significant breakthrough insight, faith was no longer understood by him as a natural preparation for grace, as the fulfillment of a condition for receiving supernatural grace by the performance of something that was within man's natural capacity to do. The soteriological scheme of Scholastic theology was synergistic, because Pelagian: God responded to man; man cooperated with God according to his native ability. Against this Pelagian synergism, Luther insisted on total inability: the utter incapacitation and absolute impotence of the natural man in abject bondage to sin. Faith therefore could not be a condition for grace, for it could not be exercised out of inherently human resources as a natural act performed of sinful man's own initiative for the purpose of man's fitting and preparing himself to be a suitable candidate for receiving grace. Faith itself could only be the result of a prevening supernatural act; it was a free gift of divine grace, resulting entirely from God's unconditioned, monergistic action. Justification thus was not obtained because of faith, merely through faith—a faith wrought in us. Rather than a cooperation of Nature and Grace (the synergism of mutual effort by both God and man), God acts unilaterally and exclusively, taking the sole initiative in a free act of sovereign grace—grace that is altogether prior to, and productive of, justifying faith. The sola fide arises out of, and is nothing other than, sola gratia.
Joseph P. Braswell