السلام عليكم ,
الجواب واضح من السؤال حيث أن الاقتباس يذكر ان "الاسراف" في طلب الدنيا هو ما يشين النفس البشرية , والمقصود من الكلام ليست كم تأكل او ما سعر ما تلبس ولكن المقصود وبوضوح شديد ان الملابس والطعام ميسرين اذا عبدنا الله حق عبادته , وادينا ما علينا والله اعلم .
لاحظ ان الاقتباس يشابه قول الله : " وفي السماء رزقكم وما توعدون فورب السماء والارض انه لحق مثل ما انكم تنطقون" وكذلك : "وما خلقت الجن والانس الا ليعبدون ما اريد منهم من رزق وما اريد ان يطعمون" .
واعتقد ايضا ان صديقك لا يفقه الكتاب اذ انه ربط بين امرين صَعُب الربط بينهما وهما : حب الدنيا والصوم , فالصوم هو ترك شهوات الدنيا المتعلقة بالطعام والفرج وقد افترى عليك يوم قال لك ما قال وما اراد الا افسادا لدينك فاحذره يرحمك الله , الله يقول : "يا ايها الذين امنوا لا تتخذوا اليهود والنصارى اولياء بعضهم اولياء بعض ومن يتولهم منكم فانه منهم ان الله لا يهدي القوم الظالمين" , لذا ان شئت اصحبه وكن عادلا معه ولكن لا تواليه كما توالي اخوانك من المسلمين .
Translation:
The answer is in the question where the quote in your question mentions that "wasting" time in seeking this world is what dirties the soul. and the Meaning is not how much you eat, or how much your cloths are, but the obvious meaning is that the way our food and cloths come to us would be made easier if we worshipped Allah truly how He deserves to be worshipped, and fulfill our duties. And Allah knows best.
Note, thethe quote your mentioned is similar to what Allah says:
And in the heaven is your provision and whatever you are promised. Then by the Lord of the heaven and earth, indeed, it is truth - just as [sure as] it is that you are speaking.
And I did not create the jinn and mankind except to worship Me. I do not want from them any provision, nor do I want them to feed Me.
Also note, that your friend does not seem to understand the bible, because he mentioned two things which really can't go together, that is the love of this dunya and fasting. Fasting is the leaving off desires of this world whether it is food or satisfaction from the wife, and he lied to you the day he said to you what he said, and he did not want anything but to corrupt your religion so beware of him Allah have mercy on you. Allah says:
يَا أَيُّهَا الَّذِينَ آمَنُوا لَا تَتَّخِذُوا الْيَهُودَ وَالنَّصَارَىٰ أَوْلِيَاءَ ۘ بَعْضُهُمْ أَوْلِيَاءُ بَعْضٍ ۚ وَمَن يَتَوَلَّهُم مِّنكُمْ فَإِنَّهُ مِنْهُمْ ۗ إِنَّ اللَّهَ لَا يَهْدِي الْقَوْمَ الظَّالِمِينَ
O you who have believed, do not take the Jews and the Christians as allies. They are [in fact] allies of one another. And whoever is an ally to them among you - then indeed, he is [one] of them. Indeed, Allah guides not the wrongdoing people.
So in conclusion, if you wish you may accompany him and treat him with full kindness, but don't befriend / be loyal to him like you are with your Muslim Brothers.