The Rebbe explains the reason why the author of this mishna uses the particular phrase כל המכבד את התורה גופו מכבד.

This chapter describes the two levels of Yirah (fear or awe of hashem) which exists within a person. The Alter Rebbe explains that the usual order is for a person to attain a lower level of Yirah which will lead to fulfillment of Torah and Mitzvot which in turns leads to a knowledge of Hashem which brings about love of Hashem. This love of Hashem in turn brings about the higher level of Yirah. The Rebbe explains near the end of the chapter that occasionally a person will first attain the level of love known as Ahavat Olam before he attains the lower of fear (Yirah Taatah). However, as he concludes this is not the normal sequence of events in one's spiritual journey.