In virtue of his firm and independent nature — partly inborn and partly developed in the severe school of experience — he felt also a pressing need of a firmly-based construction of his theo logical views, and of a clear, distinct, and unambiguous ex pression of the same. This need was in part met by the Lutheran form of doctrine. It is true, he saw very clearly the defects and imperfections which a scientific construction and demonstration of this doctrinal formula bring to light; taking into consideration, however, its essential features, he found in it the purest and truest didactic presentation of evangelical truth.* To preserve this form of the truth in its main features.