Love your fellow Jew
You probably have heard the famous saying of Rabbi Akiva: V'ahavta l'reacha kamocha. Love your fellow as yourself.
Right now we are in the time of sefirat haomer, counting the omer until the holiday of Shavuot. But during the omer is also the time when 24,000 students of Rabbi Akiva died from a plague because they did not respect each other properly: they did not leave room for another's opinion or idea. They each thought they were right and their opinion was the only one that counted. And for that they were severely punished. That is why these days are considered a time of mourning.
Rabbi Akiva was famous for the idea of ahavat yisrael.
But how do we love our fellow Jew?
First by realizing Hashem created each person and each person has a mission, a journey, and nobody takes away from anyone else. There is no reason to feel jealous or inferior to anyone else. Each of us has our own strengths and weaknesses and we each become better through the other. We can learn from everyone. We can respect and appreciate everyone even if they dont agree with us or share our opinion.
By realizing that Hashem loves each person we also can come to love each person.
We need to do what it says in Tanya: to look past the body and physical matters that divide us and to see the soul, the common spirituality we share. In that way we can fulfill the mitzva of ahavat Yisrael.