Jewish tradition identifies being slow to anger as a quality of God. In the Mussar teachings, anger is not considered an inherently negative characteristic but it is surely counter to holy aspirations to lash out in anger without some measure of reflection. Being slow to anger gives a person the time and space needed to consider how to respond, and so spares him or her all the unfortunate outcomes that acting rashly tends to bring.

Alan Morinis in Every Day, Holy Day