The scripture is against ANGER,but there is what we called HOLY anger. When you are angry against Sin or any evil things which God does not like,it is called HOLY Anger.
Jesus was angried with those people who were buying and selling in those days in His Father House i.e in the temple of God which was supposed to be House of prayer ( used for prayer). Jesus chased out those people who were buying and selling out of the temple. He turned down the tables of those money exchangers. He gathered them again after He has cleansed His Father House and He healed those who were sick.
Let us now consider the Anger of PHINEHAS which turned away the wroth of God away from the people of ISREAL. It happened that the people of Israel turned from worshipping Almighty God and they started worshipping another god(Baal).The story is in the book of Number chapter 25 verse 1-18. As a result of their actions to follow and worship another god. God anger was kindled against them. Many of them died as a result of they serving another god.There was a great plague killing the people of Israel. Those that died in the plague were about twenty and four thousand
The people of Israel were still in this situation when one of the children of Israel came and brought unto his brethren a Medianitish woman in the sight of Moses and in the sight of all the congregation of the children of Israel,who were weeping before the door of the Tabernacle of the congregation. And when PHINEHAS the son of Eleazer, the son of Aaron the priest ,saw it,he rose up from among the congregation,and took javelin in his hand and he went after the man of Israel into the tent,and thrust both of them through,the man of Isreal, and the woman through her belly. So the plague was stayed from the children of Isreal.
PHINEHAS was angry because all the people of Isreal were still in sorrow due to the death of many people and one man who was supposed to be sorrowful with them and begging God to have mercy on them,just went out to bring a strange woman to their midst to commit adultery.
This incident was not pleased to Him and he took his javelin to slay both of them. This action of his turned away the wroth of God from the people of Isreal and the plague ceased.
Although anger is not a good thing,but here his anger against Sin turned away the wroth of God and saved them form God punishment.