381. That 'tilling the ground' means cultivating this schism or heresy is clear from the meaning of 'the ground', dealt with already just above. That 'not yielding its strength' means its being sterile is evident from what has just been said about 'tilling the ground' and from the very words themselves, as well as from the consideration that people who profess faith devoid of charity profess no faith at all, as has been stated.