Sin obscures. So does selfishness. The cross purifies. All of us ordinary mortals are wounded, immersed in our own darkness. A healthy self-denial sensibly practiced and rightly motivated slowly lifts one out of his egoism, laziness, hedonistic inclinations. We are fitted to receive the clean light of the Spirit.
The saints invariably possessed a remarkable wisdom. Even the most simple of them were gifted with a penetration into reality and into the God of all reality that books and studies cannot produce. This penetrating gaze into the real was made possible by their prior purification. This must be at least part of the meaning of that mysterious saying of St. John of the Cross: “The purest suffering produces the purest understanding.” In another place the saint amplifies this idea when he remarks that “the purest suffering brings with it the purest and most intimate knowing, and consequently the purest and highest joy, because it is a knowing from further within.” One who lives the paschal mystery, life through death, lives more and more deeply and thus will see more and more penetratingly. Authenticity is begotten on the cross.
Suffering reduces us to our own ashes; it strips away egoism and makes love possible. A Scripture commentator can remark that “to be a ‘tried’ Christian or to experience the Spirit is one and the same. Trial disposes to a greater gift of the Spirit, for He now achieves by trial His work of liberation. Thus freed, the tried Christian knows how to discern, verify, ‘try’ everything.”
If adaptation to the modern world has actually meant settling for a more comfortable life, a rejection of the hard road and the narrow gate, it is no renewal at all. If updating in a religious congregation has consisted largely of mitigations, we have a clear sign of resistance to the Spirit of the living God. If the renewal of moral theology consistently means more pleasure and less sacrifice, it is no updating at all. It is a surrender to the world.
from Authenticity: A Biblical Theology of Discernment by Fr. Thomas Dubay, S.M., “Moral Behavior: Cross-Asceticism”