Recently, I have studied and contemplated Ahavas Yisroel, literally meaning "love of a Jew". For context, it is known that Ahavas Yisroel is one of the mitzvos of the Torah, incumbent on every Jew.
It was surprising to learn that one need not only love and show kindness to other Jews for him/her as a person, but also for their ruchnius, or spirituality. This means that one need not only assist another financially, if need be, but assist them with their spiritual growth, as well.
Since there are both physical and non-physical mitzvot, this charge has novel implications. With physical mitzvos, such as Tefillin or Mezuzah, this charge certainly means to encourage a fellow Jew to grow in these regards, when one sees an opportunity to do so. When it comes to non-physical mitzvos, such as simcha, or joy, merely spending time with another Jew in a way they will enjoy would indeed count.
For additional ideas, here are other mitzvot and how one can apply Ahavas Yisroel to them:
The mitzvah to belief in G-d : Gradually and gently encouraging another Jew to believe in G-d
To learn Torah: Inviting another Jew to a regular Torah class or even to learn Torah on the phone with them once a month
Shabbat meal: Inviting another Jew to your home for a traditional Shabbat meal
Lastly, it is important to remember that another Jew is not a means to an end; he is our own brother, and deserves all the same consideration we give ourselves, as the Torah says, "love your fellow as yourself”.