With the Catholic faith it would have found expression in the religious life, as she sometimes said herself.

The faith she had made her most earnest and devout, according to her light." Mrs.Georgiana Bruce Kirby, who spent a month at the house in Rutgers Street just after Isaac finally returned from Brook Farm, when Mrs.Hecker was in the prime of middle life, speaks of her as "a lovely and dignified character, full of 'humanities.' She was fair, tall, erect, a very superior example of the German house-mother.

Hers was the controlling spirit in the house, and her wise and generous influence was felt far beyond it.

She was a life-long Methodist, and took me with her to a 'Love Feast,' which I had never witnessed before." To the good sense, good temper, and strong religious nature of Caroline Hecker her children owed, and always cordially acknowledged, a heavy, and in one respect an almost undivided, debt of gratitude.
Neither Engel Freund nor John Hecker professed any religious faith.
The latter was never in the habit of attending any place of worship.
Both were Lutheran so far as their antecedents could make them so, but neither seems to have practically known much beyond the flat negation, or at best the simple disregard, of Christianity to which Protestantism leads more or less quickly according as the logical faculty is more or less developed in those whose minds have been fed upon it.

However, there was nothing aggressive in the attitude of either toward religious observance.