Calvin's teaching has never been for shrinking violets, nor is John Calvin himself thought of as "soft." He uses strong language about those who are enemies of the gospel ("pigs," "dogs").
In discussing church discipline he notes the special responsibilities borne by pastors (some are not sufficiently watchful, others tend to be over-lenient). But he also grants that pastors are often hindered from consistency by those who belong to the church they serve. The truth is, elders can turn down the thermostat of a congregation virtually at will. Yet Calvin is also concerned about Christians who acts in haste and without grace and precipitously separate from the church because of its faults. The individual dare not do that simply out of personal whim or a unilateral declaration of independence. He is, after all, a member of the church, not a lone-ranger believer. Unwise zeal, pride and arrogance, false views of holiness (or, more accurately, false views of other's holiness or lack thereof) need themselves to be disciplined.
Separation from the visible church is, therefore, to be considered only when it actually ceases to be the visible church--for in its very nature its sanctity is mixed with ongoing sin and failure. Thus, when the Prophets, the Apostles, and the Savior himself are considered, we learn a biblical balance of commitment to truth with commitment to the imperfect community. It is inexcusable for an individual to abandon the church so long as it remains a real church.
Forgiveness is always a watchword in church life. Calvin strikingly points out the significance of words many of us recite every Lord's Day: "I believe in the holy catholic church, the forgiveness of sins . . ." The former (church) is the context in which the latter (forgiveness) is realized. The very forgiveness by which we enter the church is the forgiveness in which we are ever and again sustained.
The 16th century Reformers fought to win back the keys of the kingdom. Calvin held that ordinarily there is no salvation outside of the church, but he did not hold that the church itself was the repository of forgiveness. No, forgiveness comes through the preaching of the gospel and its application to the conscience through the ministry of the Holy Spirit. Rome, therefore, had usurped the role of the word of God and the Spirit of God.
God's people stand daily in need of forgiveness and an ever-deepening assurance that they are forgiven. All sins repented of may be forgiven. This is the testimony of the patriarchs, of David, of the prophets, of Simon Peter and of all Scripture. There is forgiveness of sins at the entry into the Christian life; but it is ever and again available to us.
Especially when we are engaged in the discipline of sinners we need to remember that its function is to lead to a fresh sense of divine forgiveness and church forgiveness and restoration. For that reason its rigor must not endanger, and then destroy, the very pardon and restoration it seeks to produce.
"Therefore," says Calvin, "in the communion of saints, our sins are continually forgiven us by the ministry of the church itself when the presbyters or bishops to whom this office has been committed strengthen godly consciences by the gospel promises in the hope of pardon and forgiveness. This they do both publicly and privately as need requires. For very many, on account of their weakness, need personal consolation."