16 We desire, however, that this Our praise be salutary. The consideration of the good which has been done must not lead to slackening which might degenerate into sluggishness; it must not issue in a vainglorious pleasure which flatters the mind; it should stimulate renewed energies so that evils may be avoided and those enterprises which are useful, prudent and worthy of praise may more surely and more solidly mature. The Christian, if he does honor to the name he bears, is always an apostle; it is not permitted to the Soldier of Christ that he quit the battlefield, because only death puts an end to his military service.
Source: Sertum Laetitiae (Vatican.va)