On the importance of the daily renewal of the Christian:
“Sin is forgiven in justification, but it still retains its roots in our heart. If the Christian therefore does not renew himself daily, his heart must soon become wild again, like a tree which is not pruned, or like a garden which is not weeded. True, in justification and regeneration we are born as God’s children, and thus the beginning according to God’s image is brought about in us. But at first we are still weak infants, who must receive their daily nourishment and strengthening in renewal if they are not to die and perish again.
“In justification we are like the one who fell among murderers. Christ indeed took pity on us and bound up our deep wounds of sin with the balm of His gracious gospel. But now, in daily renewal, we must remain under the treatment of His Holy Spirit until we are fully healed when He returns and calls us to Himself by a blessed death out of the hospital of this world. Justification and the new birth are the spiritual creation. The daily renewal of the Christian is the work of spiritual preservation. However, just as the created world would long ago have perished but for God’s preservation and government, a Christian cannot remain regenerated but for daily renewal. It is indeed well if faith has once been implanted in the heart, but then it requires daily watering, as Paul says. In this way the Lord grants also the final increase for final apprehension and enjoyment of eternal life.
“Hence, what is daily renewal? It is the continuation of the work of grace begun by the Holy Spirit in our soul in justification by faith. It is the heartfelt diligence of the faithful Christian to put off the old man increasingly every day, that is, increasingly cast off all error, and to weaken, restrain, and kill sin in himself more and more. It is the daily earnest concern of a child of God to put on increasingly the new man, that is, to grow in all doctrine and knowledge and spiritual wisdom and experience, and to become more and more conformed to the image of Jesus Christ in thoughts, words, attitudes, and works.”
HT: Pastor Alms