Phinehas was one of the judges commanded by Moses to kill those who had joined Moab and turned against Yahweh. Moses in turn, had been commanded by Yahweh. Who told the Maccabees or Esther?
I think you should reread that parsha.
Phinehas was the grandson of Aaron, the great grandnephew of Moses, a Priest.
1 And Israel abode in [bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse]tim, and the people began to commit harlotry with the daughters of Moab.
2 And they called the people unto the sacrifices of their gods; and the people did eat, and bowed down to their gods.
3 And Israel joined himself unto the Baal of Peor; and the anger of the L-RD was kindled against Israel.
4 And the L-RD said unto Moses: 'Take all the chiefs of the people, and hang them up unto the L-RD in face of the sun, that the fierce anger of the L-RD may turn away from Israel.'
5 And
Moses said unto the judges of Israel: 'Slay ye every one his men that have joined themselves unto the Baal of Peor.
'
6 And, behold, one of the children of Israel came and brought unto his brethren a Midianitish woman in the sight of Moses, and in the sight of all the congregation of the children of Israel, while they were weeping at the door of the tent of meeting.
7 And when Phinehas, the son of Eleazar, the son of Aaron the priest,
saw it, he rose up from the midst of the congregation, and took a spear in his hand.
8 And he went after the man of Israel into the chamber, and thrust both of them through, the man of Israel, and the woman through her belly. So the plague was stayed from the children of Israel.
9 And those that died by the plague were twenty and four thousand.
10 And the L-RD spoke unto Moses, saying:
11 'Phinehas, the son of Eleazar, the son of Aaron the priest,
hath turned My wrath away from the children of Israel, in that
he was very jealous for My sake among them, so that I consumed not the children of Israel in My jealousy.
12 Wherefore say: Behold, I give unto him My covenant of peace;
13 and it shall be unto him, and to his seed after him, the covenant of an everlasting priesthood; because
he was jealous for his God, and made atonement for the children of Israel.'
G-d knew his heart, he wasn't told by Moses to do this. The L-RD made a covenant with him , one that many don't even know about or recognize because of his zeal for the L-RD. It was done without being told to.
Even King David extols his initiative when Moses didn't know what to do.
Psalms 106
21 They forgot God their saviour, who had done great things in Egypt;
22 Wondrous works in the land of Ham, terrible things by the Red Sea.
23 Therefore He said that He would destroy them, had not Moses His chosen stood before Him in the breach,
to turn back His wrath, lest He should destroy them.
24 Moreover, they scorned the desirable land, they believed not His word;
25 And they murmured in their tents, they hearkened not unto the voice of the L-RD.
26 Therefore He swore concerning them, that He would overthrow them in the wilderness;
27 And that He would cast out their seed among the nations, and scatter them in the lands.
28 They joined themselves also unto Baal of Peor, and ate the sacrifices of the dead.
29 Thus they provoked Him with their doings, and the plague broke in upon them.
30 Then stood up Phinehas, and wrought judgment, and so the plague was stayed.
31 And that was counted unto him for righteousness, unto all generations for ever.
