Hillel was known to say:
“Be of the disciples of Aharon,
loving peace and pursuing peace,
loving people and bringing them closer to Torah

“Two men were fighting  with each other.

Aharon went and sat with one of them
and said to him:
My son, see what your friend said?
His heart is distraught
and he tears his clothes and says:
‘Woe is me!
How can I lift my eyes and see my friend?
I am so ashamed that it was I who hurt him!’

This is how he sat with him
until all jealousy was removed from his heart.

Then  Aharon went  and sat with the other
and said to him:
My son, see what your friend said?
His heart is distraught
and he tears his clothes and says :
‘Woe is me!
How can I lift my eyes and see my friend?
I am so ashamed that it was I who hurt him!’
This is how he sat with him until all jealousy was removed from his heart.

And when they met each other,
they hugged and kissed each other.”

(Avot D’Rabbi Nathan)