It was not that the Holy was not greater than the unholy as you put it -but that humanity needed to learn and know the difference (though this too needed further work - since man went too far one can say in such…as Jesus then brought to fulfillment and correction).
After the fall of man - the pedagogy of God was a slow process step by step forward… until the time was right for the incarnation of the Logos (Jesus Christ the Son of God). So his people had to come to realize the reality of God, of Holiness, of being set apart from the corruption that had spread through civilization.
53 The divine plan of Revelation is realized simultaneously “by deeds and words which are intrinsically bound up with each other” and shed light on each another. It involves a specific divine pedagogy: God communicates himself to man gradually. He prepares him to welcome by stages the supernatural Revelation that is to culminate in the person and mission of the incarnate Word, Jesus Christ.
St. Irenaeus of Lyons repeatedly speaks of this divine pedagogy using the image of God and man becoming accustomed to one another: The Word of God dwelt in man and became the Son of man in order to accustom man to perceive God and to accustom God to dwell in man, according to the Father's pleasure.