Final answer:
The provided texts do not specify which position Antiochus sold, but historically, various positions of power such as governorships or military commands could have been traded for financial support.
Step-by-step explanation:
The position that Antiochus sold to the highest bidders is not explicitly mentioned in the provided references. However, during the ancient times, it was common for positions of power and certain offices to be sold or traded for favors, often under the guise of donations or contributions to the state. Based on historical context, one could infer that positions such as governorships, priesthoods or even military commands could have been subject to such practices in the Hellenistic kingdoms, including the Seleucid Empire. This was a period characterized by political intrigue and frequent warfare, where financing campaigns and securing loyalty often took precedence over meritocratic appointments.