Obadiah was a prophet of israel who predicted the complete destruction of the edomites, descendants of esau.

Yes Obadiah or slave of God propheseed against Edom but he was a convert Edomite. He converted into Judaism and preached in favor of just one God.

2018 means 2018 ce or common era

there have been other eras too including bce, which included way more years.

im not sure its either a leader of a group of congresspeople or a person from a congressmans district

sorry im not sure