The emanated being {i.e. the creature} must crave abundance. Only then can we say that the will to receive is actually manifested by the emanated one. It is only possible for this craving to occur when a lack is felt... at that moment the vessel of recipiency is permanently completed.
Recall that all extension of Light from the Emanator {i.e. God} contain both a will to receive and a will to impart... When this will to impart is revealed by the emanated being {i.e. the creature, through the conversion of his will to receive into a will to impart}, it eventually evokes the extension of the Emanator's ample Light, which comes as if by invitation of the newly arisen will {to impart}. This extended Light is defined in every space as the Light of Mercy, or Grace. {In contrast} the first extension from the Emanator of Light, in which is included the will to receive, is always called the ... Light of Substance {because first Light creates the substance which makes up the vessel or creature}.
(p. 69-70)