Tenebra is the Latin word for “darkness” and the three pre-Lent Sundays of the “Gesimas” emphasize the approaching darkness which shall come on Good Friday. Septuagesima(last week) simply means “70 days” and in the same way, Sexuagesima means “60 days.” As Lent is 40 days of exile with Jesus, so the 70, 60 and 50 days of pre-Lent anticipate the impending darkness of the Good Friday cross.
But now, we see how even the darkness of our false worship is overcome there on Calvary, foreshadowed of old by the high priest of Israel, Aaron, required as he was to make atonement for his own sons and their guilt. In the same way, our Lord Jesus entered the temple to purify and cleanse it, to make it once again the most holy place of all, that is, the place where God dwells.
Since Jesus is God, that holy place is wherever he is now, risen with the power of immortality. He enters you, according to his promises and especially by means of the gift of Bread and Wine, to be your Light in the Darkness and your guide in the Valley of the Shadow.