Ezra 4:6 KJV

And in the reign of Ahasuerus, in the beginning of his reign, wrote they unto him an accusation against the inhabitants of Judah and Jerusalem.

AhasuerusThe Cambyses of secular history (529-521 BC); not the Ahasuerus of Esther, who is the Xerxes of secular history (485 BC). (See Scofield "Dan 5:31").

The building of the temple is hinderedIt is an old slander, that the prosperity of the church would be hurtful to kings and princes. Nothing can be more false, for true godliness teaches us to...

Esther 1:1 Now it came to pass in the days of Ahasuerus, (this is Ahasuerus which reigned, from India even unto Ethiopia, over an hundred and seven and twenty provinces:)
Daniel 9:1 In the first year of Darius the son of Ahasuerus, of the seed of the Medes, which was made king over the realm of the Chaldeans;
Matthew 27:37 And set up over his head his accusation written, THIS IS JESUS THE KING OF THE JEWS.
Acts 24:5–9 For we have found this man a pestilent fellow, and a mover of sedition among all the Jews throughout the world, and a ringleader of the sect of the Nazarenes: …
Acts 24:13 Neither can they prove the things whereof they now accuse me.
Acts 25:7 And when he was come, the Jews which came down from Jerusalem stood round about, and laid many and grievous complaints against Paul, which they could not prove.
Revelation 12:10 And I heard a loud voice saying in heaven, Now is come salvation, and strength, and the kingdom of our God, and the power of his Christ: for the accuser of our brethren is cast down, which accused them before our God day and night.

From OpenBible.info, most relevant first.

Accusation, false Against Jews, returned under Ezra
Falsehood Samaritans, in their efforts to hinder the rebuilding of the temple at Jerusalem
Israel, prophecies concerning Temple rebuilt and dedicated
Joshua Assists Zerubbabel in restoring the temple
Malice Samaritans toward the Jews
Persecution Of the Jews
Temple Restored by Zerubbabel

AhasuerusThere are three kings designated by this name in Scripture. (1.) The father of Darius the Mede, mentioned in Dan 9:1. This was probably...
JudahPraise, the fourth son of Jacob by Leah. The name originated in Leah’s words of praise to the Lord on account of his birth: “Now will I...
JerusalemCalled also Salem, Ariel, Jebus, the “city of God,” the “holy city;” by the modern Arabs el-Khuds, meaning “the holy;” once “the city of...

And in the reign וּבְמַלְכוּת ûbĕmalkût מַלְכוּת Noun · feminine singular construct · with and, preposition
of Ahasuerus אֲחַשְׁוֵרוֹשׁ ʾăḥašwērôš אֲחַשְׁוֵרוֹשׁ Proper name
in the beginning בִּתְחִלַּת bitḥillat תְּחִלָּה Noun · feminine singular construct · with preposition
of his reign מַלְכוּתוֹ malkûtô מַלְכוּת Noun · feminine singular construct · with suffix: third person masculine singular
wrote כָּתְבוּ kātĕbû כָּתַב Verb · qal perfect, third person common plural
they unto him an accusation שִׂטְנָה śiṭnâ שִׂטְנָה Noun · feminine singular
against the inhabitants עַל ʿal Preposition יֹשְׁבֵי yōšĕbê יָשַׁב Verb · qal active participle, masculine plural construct
of Judah יְהוּדָה yĕhûdâ יְהוּדָה Proper name
and Jerusalem וִירוּשָׁלִָם wîrûšālim יְרוּשָׁלַ͏ִם Proper name · with and

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