Our first parents Adam and Eve found themselves tempted by the fruit of the tree of the knowledge of good and evil. The text of Genesis tells us exactly what it was about the fruit that made it so desirable. It was a “delight to the eyes,” “good for food,” and “desirable to make one wise.”
“So when the woman saw that the tree was good for food, and that it was a delight to the eyes, and that the tree was to be desired to make one wise, she took of its fruit and ate; and she also gave some to her husband, and he ate.” (Gen 3:6)
St. John describes this threefold temptation as “the lust of the flesh, the lust of the eyes and the pride of life (1 Jn 2:16).” Because it was these attributes of the fruit that our first parents lusted after, Human nature seems to be affected by the threefold lust (1 Jn 2:15-16).
Back in the sixth century Pope Gregory the Great pointed out that Satan would later use these same temptations in an attempt to bring about the fall of the new Adam, Jesus (Matt 4:1-11, CCC 538):
“the means by which he overcame the first man were the same ones that caused him to yield when he tempted the second Adam. The devil tempted him by gluttony[lust of the flesh] when he said, “Tell these stones to become bread.” He tempted him by vain ambition when he said, “If you are the Son of God, cast yourself down.” He tempted him by an avaricious desire for high position when [pride of life] “he showed him [lust of the eyes] all the kingdoms of the world, saying, ‘I will give you all these if you will fall down and worship me.’ ” But the devil is overcome by the second man in the same way as he boasted of overcoming the first man. He exits our heart at the same juncture where he first made his earliest inroads.” (forty Gospel homilies, 16:2-3)
Unlike our first parents Jesus resists and rebuffs these temptations. Rather than lusting after food, Jesus abstained from food and rather than succumbing to pride, Jesus humbles himself in prayer, putting his trust in his Father.
In the Sermon on the Mount, Jesus gives us the tools to combat the threefold lust:
Fasting (Matt 6:16-18) – Fasting trains us to renounce earthly pleasures and thus combats the lust of the flesh.
Almsgiving (Matt 6:2-4) – Giving away helps to combat the lust of the eyes (seeing something and wanting to take it).
Prayer (Matt 6:5-7) – Getting down on your knees and humbling yourself combats pride.
Dr. Tim Gray and Jeff Cavins explain it well in their excellent book ‘walking with God’:
"With God’s grace, almsgiving, prayer, and fasting overcome the threefold wounds that human nature grapples with after the Fall: “The lust of the flesh and the lust of the eyes and the pride of life, is not of the Father but is of the world” (1 Jn 2:16). The lust of the flesh—an inordinate desire for luxury and comfort—is combated with fasting, the willingness to sacrifice for a higher good. The lust of the eyes—a covetousness and inordinate desire to possess for oneself the good things of this world—is countered by almsgiving. Pride of life is countered by a life of prayer, in which we see that God, and not ourselves, is the author of our life. (Walking with God: A Journey through the Bible, p. 246).
