The third mishnah of Pirkei Avot focuses on motivations for serving God and includes some very interesting language.
1:3 – Antigonus of Socho received [the Torah] from Simon the Righteous. He used to say: Be not as servants who serve the master on condition of receiving a reward; be rather as servants who serve the master not upon the condition of receiving a reward; and let the fear of Heaven be upon you.
On the whole, the Jewish tradition asserts that we will be rewarded — be it in this world or the next — for faithfully following the commandments, but Antigonus is concerned about making this the primary reason for serving God.
Oddly, however, it’s not clear whether he tells us what the motivation for serving God should be. Antigonus should have said something like: “Be not as servants who serve the master on condition of receiving a reward; be rather as servants who serve the master out of love…or faithfulness…or responsibility…or something else.”
Instead, Antigonus suggests that we serve God “not upon the condition of receiving a reward” — not a positive motivation, but a negative of one.
So what motivation does Antigonus suggest?
One answer may be related to the final line of the mishnah “and let the fear of Heaven be upon you.” Perhaps Antigonus is suggesting that yirat hashem, fear, be the primary motivation for following God. To make this a little more easy to stomach, it should be noted that Abraham Joshua Heschel (and others) suggested that “awe” and not “fear” is the correct translation of yirah.
More likely, perhaps, is the possibility that Antigonus wasn’t citing “the fear of Heaven” as synonymous with the correct motivation, but rather a necessary addendum to it.
And perhaps Antigonus purposely left the proper motivation ambiguous. In this reading Antigonus’ message could be understood as follows: Whatever your motivations for serving God, do not do it for the reward — but no matter what your chosen motivation is, be sure that it is accompanied by an “awe of heaven.”