Cursed at the Final Judgement
Anathema Maranatha is written by Paul in 1 Corinthians:
1 Cor 16:22 [KJV]
If any man love not the Lord Jesus Christ, let him be Anathema Maranatha.
Paul is basically saying that if a man doesn’t love Jesus Christ he will be appointed unto eternal damnation when the judgement day for unbelievers happens. This will be at the White Throne Judgement which occurs after the Second Coming, and after the casting out of the unbelievers that are still alive during the Great Tribulation (7 year period at the end of this world) that worshipped the Beast or its image and/or took the mark of the Beast. After that we have Jesus ruling on earth in Jerusalem for 1000 years then the White Throne Judgement will happen.
So to say Anathema Maranatha is the same as saying “Cursed at the Final Judgement”.
μαράν ἀθά maran atha