It is a model of brief statement of great truths, and proves that the social difficulty can only be fully remedied by the Catholic Church, which has an elevating force incomparably more powerful than any other known to humanity.

The method used and the choice of arguments are peculiarly Isaac Hecker's own, and the tone, though affectionate, is one of authority, as that of an exponent of evident truth.

His letters to his mother and his brothers are full of controversy, abounding in appeals to Scripture, to the voice of conscience, to the dictates of reason; and although the tone is one of deep affection, the attacks on Protestantism are keen, and the use of facts and persons as illustrations full of intelligence.

Most of the letters which we have found were addressed to his mother, for whose conversion he had an ardent longing.

With one of them he sends her a little manuscript treatise on true Bible Christianity which he had himself prepared.