What is the one great event associated with Sinai in Arabia?
The one great event associated with Sinai in Arabia is the giving of the Ten Commandments. Paul uses Hagar as a picture of Mount Sinai, where the Law was given. This event is tied to the Law, which brought bondage rather than the promise.
In Galatians 4:25, Paul says Hagar is typically of Mount Sinai in Arabia. Les explains that the one great event always associated with Sinai in Arabia is the Ten Commandments. Hagar is a picture of the giving of the Ten Commandments on Mount Sinai. Paul is using the same analogy that the Law was the flesh, like a yoke, and it only brought in bondage. So Hagar speaks of the Law as it was given at Sinai, which was still indicative of Temple worship at the time Paul wrote Galatians, about A.D. 60, ten years before the Temple was destroyed in A.D. 70.
For this Agar is mount Sinai in Arabia, and answereth to Jerusalem which now is, and is in bondage with her children.