What if my sole purpose in life is to hold open the door for an old lady? While I'm not mocking this and I'm sure it is a tremendous service to her more so than me, where does that leave me mentally and morally? That seems a bit depressing. Is it worth it just for that? I would appreciate any torah clarification on this matter.
In case you're worried I'm not contemplating suicide.
You don't know the purpose of your life. But there is one, and you must discover it. Rav Nachman of Breslov used to say: "The day that you were born is the day God decided the world could not continue without you." Chances are it's not as simple as in your example and you may not know it even at time of death, but it was there.
Everything that exists has a purpose. Every person could play a critical role in Hashem's Plan.
R Shimon Shkop writes in the introduction to Shaarei Yosher (tr. mine from Widen Your Tent, Mosaica Press, 2019):
If his feelings are broader and include [all of] Creation, that he is a great person and also like a small limb in this great body, then he is lofty and of great worth. In a great machine, even the smallest screw is important if it even serves the smallest role in the machine. For the whole is made of parts, and no more than the sum of its parts.
Think of a small screw holding together the casing of an engine. If that screw is too loose, the casing will leak oil, the engine will overheat, and melt itself into a useless lump of metal. A little looser, the engine can shake itself apart. That screw is just as critical to the engine as the parts that come up in driver's ed on engine repair, like the pistons or the spark plugs. The machine is useless without either.
The problem most of us have is a lack of anavah and tzeni'us, a healthy level of self-esteem and not needing to grab the spotlight. We all want to be flashy spark plugs, and are unhappy if all we will accomplish in life is quietly holding the engine casing together.
If Hashem created a human being for the sake of holding open the door for an older woman, rest assured that is a critical part of the Ddivine Plan. Otherwise, He could have addressed the woman's need without making a person, a whole Tzelem Elokim ("image" of the Divine) to do this job. The engine of history couldn't run without it.
The Zohar states:
דודאי לא ברא קודשא בריך הוא מלתא דלאו איהו צריך
It's certain that The Holy One blessed be He didn't make anything He didn't need.
Everyone is needed; everything has an infinitely significant purpose.
Note the subtle point here. If a person was created for their own need, that's circular1, arbitrary2, and pathetic; it means their life is ultimately meaningless, and they are needy - a bit like a pet, ch'v. This is the root of much if not all neuroticism. See Chassidic Discourses Vol 1:18. for an in depth discussion of why a human is an intrinsically purposeful creature.
This purpose breathes life and vitality into everything else, otherwise it would all just be הבל הבלים, vanity. The pursuit of happiness, pleasure, satisfaction, self determination and mastery of one's life will fall hollow and empty in the end, without it.
It is infinitely better, morally and mentally, to be needed, vs being needy.
Note that we all have a general purpose (fulfilment of the Mitzvot), as well as more specific ones as well, such as our tikun, our yiud etc. Statements of "you were created to open that one door for that one lady" do not imply you are not intrinsically necessary in and of yourself. As Rambam says in Moreh Nevuchim 3:13:
שלא באר כלל בדבר מהם שיהיה בעבור דבר אחר, אלא כל חלק וחלק מחלקי העולם – זכר שהוא המציאו ושמציאותו היה נאות לכונה
For no part of the creation is described as being in existence for the sake of another part, but each part is declared to be the product of God’s will, and to satisfy by its existence the intention [of the Creator]
See ספר השיחות - ה׳תנש״א on כי תבוא for an exquisite explanation of how Hashem desires us, ourselves, rather than as a means to an end.
So, statements like the one you've brought about the old lady need to be given their proper context, as they can't mean that you are otherwise unnecessary - you are. So what they really mean is that, even if you waste your whole life, except that one small act of kindness, it still was worth it for you to be born because it was significant, and only you could have done it. Worth it for you, for her, for all of Klal Yisrael, and above all: for Him.
1 - Pirkei Avot 4:22: "you didn't choose to be made"
2 - See this answer for discussion on the evil of arbitrariness
According to the Arizal, no one reincarnates (and since the destruction of the Beit HaMikdash, may it be rebuilt speedily in our days, we are all reincarnations) to do a single task, but, rather, we have multiple missions in life and one main mission.
What's more, you can miss your main mission in life and still do amazing things.
How can I prove this? In Shar HaGilgulim, Gate 33, Chapter 2, Rabbi Chaim Vital writes in the name of the Arizal, "After that, he [Haran, Abraham Aveinu's brother] reincarnated into Aharon to rectify the aforementioned sin, but just the opposite occurred when he sinned in the incident of the calf. He should have been killed; it was fitting that he give himself over to be killed when the Mixed Multitude came to him and said,"Arise and make a god for us"(Shemot"32:1).Translation by Rabbi Pinchas Winston.
So let that sink in for a moment. Aharon HaCohen's main mission in life was to allow himself to be killed rather than create the Golden Calf. He did not succeed at this mission. Did he still go on to do great things? Of course!
In your specific case, we can be sure (in Arizalian kabbalah, if not in other systems) that you did not come into this world just to hold the door open for an old lady on June 3rd, 2025. And we can further be sure that even if that's the main mission you're here for and you blow it, you can still do amazing things in life!
I would argue that favor was significant if someone was sent into the world to do it. This reminds me of an excerpt from hayom yom.
'The Alter Rebbe received the following teaching from the tzadik Reb Mordechai, who had heard it from the Baal Shem Tov: A soul may descend to this world and live seventy or eighty years, in order to do a Jew a material favor, and certainly a spiritual one."
