Likkutei Torah associates this concept with our Sages' statement: "All the prophets began their prophecies with äï (gematria 25) "So the L-rd has spoken;" Moshe began his prophecies, "This is the word of G-d."
The difference between "So" and "This" is that stating "this" implies that the person actually sees the subject he is speaking about. To quote our Sages, "he can point his finger and say, 'This is it.' " In contrast, "So" implies that one does not actually see the subject which one is talking about. Though one perceives it, the perception is not through actual sight.
These two levels are reflected in the creation of man. The Torah relates that man was created, "in our form and in our image." "Our form" means possessing the form of G-d (equivalent to the level of "This"). "Our image" refers to a lower level, something which resembles G-dliness (the level of "So").
This characterizes the difference between the 25th of Elul and Rosh HaShanah. The creation of the entire world on Rosh HaShanah is related to the level of "our image." In contrast, on Rosh HaShanah, the inner intent and the "soul" of the entire creation was revealed with the creation of man. The Torah begins Bereishis implying that the world was created for two entities which are called "first," Israel and the Torah. This is equivalent to the level "our form."
The concept of creation is relevant to each person as an individual. Indeed, man was created alone -- in contrast to the other creatures who were created in pairs -- to teach each one of us that we are obligated to say, "The world was created for me;" i.e., that the responsibility for the entire world is his as an individual. Accordingly, the above concept must produce a lesson in our service of G-d.
The two levels, "our form" and "our image," are also reflected in the Torah and in the mitzvos. There are some mitzvos, for example the mitzvos associated with the Beis HaMikdash, which in the time of exile can only be fulfilled in a manner of "our image." Though "our lips compensate for [the sacrifice of] bulls," i.e., our study of these laws is equivalent to the fulfillment of the mitzvos, this is not the full dimension of the mitzvos' performance. There are other laws which even in the time of exile can be fulfilled in a complete manner, "our form."
It is appropriate that in the month of Elul, the month of stock-taking, that we think over whether we have fulfilled these services in the fullest degree possible. Through the complete fulfillment of both of these services in the time of exile, we will merit the building of the Beis HaMikdash in the Messianic Era when we will fulfill both these services on a higher level.