The same sun that softens butter hardens clay

The nature of God's Word is that whosoever read it or hear it reasoned and disputed before him, it will begin immediately to make him every day better and better, till he be grown into a perfect man in the knowledge of Christ and love of the law of God; or else make him worse and worse, till he be hardened that he openly resist the Spirit of God, and then blaspheme after the example of Pharoah, Korah, Abiram, Balaam, Judas, Simon Magnus and such other. 

(Documents of the English Reformation, ed. Gerald Bray, Tyndale's Preface to the New Testament, p21)

..he that hath a good heart toward the Word of God and a set purpose to fashion his deeds thereafter and to garnish it with godly living and to testify it to other(s), the same shall increase more and more daily in the grace of Christ. But he that loveth not, to live thereafter and to edify other(s), the same shall lose the grace of true knowledge and be blinded again and every day wax worse and worse and blinder and blinder, till he be an utter enemy of the Word of God and his heart hardened, that it shall be impossible to convert him. 

(Documents of the English Reformation, ed. Gerald Bray, Tyndale's Preface to the New Testament, p21-22)