Refining of the holy sparks is through chochmah - deception (אני חכמה שכנתי ערמה) | Refining sparks when eating happens when he eats not for self gratification but rather for the sake of serving God with the energy he gets from eating | Working on yourself not to desire the physical takes away the feeling of pleasure when eating | Physical pleasure from eating causes great spiritual decent ones soul | A lower level of connecting to God's oneness | Uplifting the sparks in food like the uplifting of a animal sacrifice on the altar | How a business man can uplift the Godly sparks in all physical things he is involved with - no prohibitions, no being a 'workaholic' | Work is only a physical 'channel' (כלי) to bring down God's blessings to this physical world | Certain special souls don't need a physical 'channel' for God's blessings, but most people do.
• Link to view this page of the maamar: http://www.hebrewbooks.org/pdfpager.aspx?req=31640&st=&pgnum=68.
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