"Paul makes this process of “recasting” even clearer by saying that we become new if we transform our way of thinking. What has been introduced here with “way of thinking” is the Greek term “nous”. It is a complex word. It may be translated as “spirit”, “sentiments”, “reason”, and precisely, also by “way of thinking”. Thus our reason must become new. This surprises us. We might have expected instead that this would have concerned some attitude: what we should change in our behaviour. But no: renewal must go to the very core. Our way of looking at the world, of understanding reality all our thought must change from its foundations. The reasoning of the former person, the common way of thinking is usually directed to possession, well-being, influence, success, fame and so forth. Yet in this way its scope is too limited. Thus, in the final analysis, one’s “self” remains the centre of the world. We must learn to think more profoundly. St Paul tells us what this means in the second part of the sentence: it is necessary to learn to understand God’s will, so that it may shape our own will. This is in order that we ourselves may desire what God desires, because we recognize that what God wants is the beautiful and the good. It is therefore a question of a turning point in our fundamental spiritual orientation. God must enter into the horizon of our thought: what he wants and the way in which he conceived of the world and of me. We must learn to share in the thinking and the will of Jesus Christ. It is then that we will be new people in whom a new world emerges.
Paul illustrates the same idea of a necessary renewal of our way of being human in two passages of his Letter to the Ephesians; let us therefore reflect on them briefly. In the Letter’s fourth chapter, the Apostle tells us that with Christ we must attain adulthood, a mature faith. We can no longer be “children, tossed to and fro and carried about with every wind of doctrine…” (4: 14). Paul wants Christians to have a “responsible” and “adult faith”. The words “adult faith” in recent decades have formed a widespread slogan. It is often meant in the sense of the attitude of those who no longer listen to the Church and her Pastors but autonomously choose what they want to believe and not to believe hence a do-it-yourself faith. And it is presented as a “courageous” form of self-expression against the Magisterium of the Church. In fact, however, no courage is needed for this because one may always be certain of public applause. Rather, courage is needed to adhere to the Church’s faith, even if this contradicts the “logic” of the contemporary world. This is the non-conformism of faith which Paul calls an “adult faith”. It is the faith that he desires. On the other hand, he describes chasing the winds and trends of the time as infantile. Thus, being committed to the inviolability of human life from its first instant, thereby radically opposing the principle of violence also precisely in the defence of the most defenceless human creatures is part of an adult faith. It is part of an adult faith to recognize marriage between a man and a woman for the whole of life as the Creator’s ordering, newly re-established by Christ. Adult faith does not let itself be carried about here and there by any trend. It opposes the winds of fashion. It knows that these winds are not the breath of the Holy Spirit; it knows that the Spirit of God is expressed and manifested in communion with Jesus Christ. However, here too Paul does not stop at saying “no”, but rather leads us to the great “yes”. He describes the mature, truly adult faith positively with the words: “speaking the truth in love” (cf. Eph 4: 15). The new way of thinking, given to us by faith, is first and foremost a turning towards the truth. The power of evil is falsehood. The power of faith, the power of God, is the truth. The truth about the world and about ourselves becomes visible when we look to God. And God makes himself visible to us in the Face of Jesus Christ. In looking at Christ, we recognize something else: truth and love are inseparable. In God both are inseparably one; it is precisely this that is the essence of God. For Christians, therefore, truth and love go together. Love is the test of truth. We should always measure ourselves anew against this criterion, so that truth may become love and love may make us truthful."
Pope Benedict XVI
vatican.va/holy_father/benedict_xvi/homilies/2009/documents/hf_ben-xvi_hom_20090628_chius-anno-paolino_en.html
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