The penultimate plague God put in Egypt before the Israelites were set free was

The penultimate plague God put in Egypt before the Israelites were set free was the Plague of Darkness. This was a supernatural darkness that covered the land of Egypt for three days, during which time nobody could see or move around. The darkness was so thick that it could be felt, and it was said to be a darkness that could be "felt". According to the Bible, the Plague of Darkness was sent by God to punish Pharaoh and the Egyptians for refusing to let the Israelites leave Egypt. The darkness was a sign of God's power and a warning to Pharaoh that he needed to obey God's command to release the Israelites. It was also a way to protect the Israelites from any potential attacks by the Egyptians during their journey to freedom. After the three days of darkness had passed, Pharaoh agreed to release the Israelites. This led to the final plague, the Plague of the Firstborn, in which the firstborn of all the Egyptians were killed, but the Israelites were spared because they had followed God's instructions to mark their doors with the blood of a sacrificial lamb. This event is commemorated in the Jewish holiday of Passover.