Unfortunately, I can’t give a straight answer to this. It is more a situation of “both…and” rather than “either…or”.
First let’s start off with what sanctifying grace is. It is a supernatural gift which uplifts man to his eternal salvation. In this case, the mere presence of sanctifying grace is infinite. It is the infinite magnitude and overabundance of the gift which raises us to eternal life. Simply because it is infinite, you can’t really have more or less sanctifying grace. You either have it or you don’t.
In this, we have addressed the gift itself. Now, we must address sanctifying grace with regards to the person who has received it. This is the area in which @Vico and @porthos11 have spoken about. While we have been given this inexhaustible gift of sanctifying grace, we can grow in our acceptance and assimilation of that grace in our own life. Every time we turn to that grace in the reception of the Eucharist, we grow in our union with sanctifying grace. I believe it may be more accurate to say that we grow in our union with the grace which has already been given to us rather than to say that we receive more grace.
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