Fulfilling mitzvos, emuna and Torah are essential in Avodas Hashem.
We see those who perform mitzvos and learn Torah. However, if they do not have proper emuna, they are still lacking a rudimentary element. Likewise, one can have emuna but may not be learning Torah or performing mitzvos. A person requires all three. These three are alluded to in חותמו של הק"בה אמת, the signet of Hashem is אמת, as אמת serves as an acronym for אמונה, מצות, תורה.
As we mentioned having just two of these three is not sufficient. This is how we can explain אם בחקתי תלכו ואת מצותי תשמרו ועשיתם אתם.
אם stands for אמונה, מצות. However, that is insufficient, as one also must have בחקתי תלכו, which Rashi says refers to toiling in Torah. The next word is ואת which translates as: and if he has just אמונה and תורה (the first letters of את), that is not enough since he also needs מצותי תשמרו, mitzva observance. מצות and תורה surely are not enough as is hinted to in its initials which spell מת.
How should we conduct ourselves? With all three, as the Pasuk continues ועשיתם אתם as אתם forms an acronym for אמונה, תורה, מצות!
