From the Word
6 Your boasting is not good. Do you not know that a little leaven leavens the whole lump? 7 Cleanse out the old leaven that you may be a new lump, as you really are unleavened. For Christ, our paschal lamb, has been sacrificed.
1 Corinthians 5:6–7, RSV
If we are to be a new, sweet lump, we must purge out the old leaven. A nature renewed by faith and Christianity will not admit of our living as we did when devoid of faith and in sin, under the influence of an evil conscience. Note the apostle’s peculiar words. He enjoins purging out the old leaven, assigning as a reason, that ye are a new and unleavened lump. By a new unleavened lump he means that faith which clings to Christ and believes in the forgiveness of sin through him; but how shall we explain the fact that he bids them purge out the old leaven that they may be a new lump, when at the same time he admits them to be unleavened and a new lump? How can these Christians be unleavened, when they have yet to purge out the old leaven?
This is an instance of the Pauline and apostolic way of speaking concerning Christians and the kingdom of Christ; it tells us what the condition really is. It is a discipline wherein a new, Christian life is entered upon through faith in Christ, the true Passover; hence, Easter is celebrated with sweet, unleavened bread. But at the same time something of the old life remains, which must be swept out, or purged away. However, this latter is not imputed, because faith and Christ are there, constantly toiling and striving thoroughly to purge out whatever uncleanness remains. Through faith we have Christ and his purity perfectly conferred upon ourselves, and we are thus regarded pure; yet in our own personal nature we are not immediately and wholly pure, without sin and weakness. Much of the old leaven still remains, but it will be forgiven, not be imputed to us, if only we continue in faith and are occupied with purging out that remaining impurity.
This is Christ’s thought when he says to his disciples, “Now ye are clean through the word which I have spoken unto you,” and in the same connection he declares that the branches in him must be purged that they may bring forth fruit. To Peter he says, “He that is washed needeth not save to wash his feet, but is clean every whit; and ye are clean, but not all.” By faith a Christian lays hold of the purity of Christ; it brings the Holy Spirit, who enables man to withstand and subdue sin.
Luther, Martin, and John Sander. Devotional Readings from Luther’s Works for Every Day of the Year. Augustana Book Concern, 1915, pp. 58–59.
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