It is written, "Tha Angel who spake in me." And yet there is a difference even here. The Angel is in us suggesting what is good, not bestowing it: stimulating us to goodness, not creating goodness. God is so in us as to give the grace and infuse it into us; or rather, so in us that He Himself is infused and partaken of, so that one need not fear to say that He is one with our substance. For you know, "He that is joined unto God is one spirit." The Angle is in the soul as a comrade, God as life.
St. Bernard: On Consideration.