Sanballat. On Sanballat and Tobiah, see on v. 10.
Geshem the Arabian. When it became evident that Sanballat was governor of Samaria (see on v. 10) and Tobiah perhaps governor of Ammon, or at least an influential leader of that nation, it was also suggested that Geshem (or Gashmu; see Neh. 6:6) might have held a similar position in the Persian province of Arabia. The latter apparently included Edom, for Edom is never mentioned by Nehemiah. This supposition is corroborated by the recent discovery of inscriptions made by the Lihyanites, who displaced the Edomites in the 5th century B.C., in which a Geshem is mentioned as after of Dedan.
Laughed us to scorn. Either by sending messengers, as Sennacherib did (2 Kings 18:17-35), or by a formal written communication.