Imperturbable Calm!
The Blessed Buddha once said:
Knowing that the
other person is angry,
The one who remains just aware and calm
acts in and for his own best interest,
and for the others' interest, too!
Samyutta Nikāya I, 162

Exalted in mind, just open,
and clearly aware,
Is the recluse trained in the ways of the sages:
One who is such, calmed
and ever mindful,
He has no sorrows!
Udana IV, 7

Calm is his mind.
Calm is his speech.
Calm is his
behaviour.
So is the
tranquillity of one
freed by the insight of right
understanding...
Dhammapada
96

More on this sweetly silenced Tranquillity
(Passaddhi):
http://What-Buddha-Said.net/drops/Forest_Bliss.htm
http://What-Buddha-Said.net/drops/IV/Silenced.htm
http://What-Buddha-Said.net/drops/III/Feeding_Tranquillity.htm
http://What-Buddha-Said.net/drops/III/Tranquillity_Passaddhi.htm