Any משפיע isn't intrinsic and self sufficient, therefore he can gain from his השפעה or be deficient from it | Light is essential and intrinsic, its shining is automatic, not invested in this act, therefore not changed by it | To be a משפיע you must put yourself into a whole different mode of giving | משפיע = being changed and affected by the השפעה, bothered by it | מאור = not changed at all by shining its light, because the light is only an external ray that is nothing compared to its source. שפע - you're giving over something of essence and substance - מהות דבר | Even though light is only a ray from its source, it is similar to its source, שפע is not similar at all - שיחות חולין של תלמידי חכמים • Link to view this page of the maamar: http://www.hebrewbooks.org/pdfpager.aspx?req=31640&st=&pgnum=30 •