What was going on in Jerusalem at the time Paul wrote Galatians?
At the time Galatians was written, around A.D. 60, Jerusalem's Temple was the center of Jewish activity. Temple worship and daily sacrifices—hundreds of them—were ongoing. This was about ten years before the Temple's destruction in A.D. 70. Sacrifices were offered daily, and the Temple dominated Jewish religious life.
Les explains that Galatians was written about A.D. 60, while the Temple was destroyed in A.D. 70. So ten years before the Temple's destruction, Jerusalem was still engaged in Temple worship, with daily sacrifices—hundreds and hundreds of them. The Temple was the very center of all Jewish activity at the time Paul wrote Galatians. Les ties this to Paul's analogy: Hagar represents Mount Sinai in Arabia, where the Ten Commandments were given, and she pictures the Law. The Law given at Sinai was still indicative of Temple worship when Paul wrote his letter to the Galatians.