Who were the signs in Egypt actually for?
The signs in Egypt were primarily for Moses and Aaron, not for Pharaoh. God used them to prove to those two men that He would supernaturally bring Israel out of Egypt. They confirmed God's promise to deliver Israel through them.
Les explains that Israel has always demanded signs, going back to Moses. When God called Moses from the desert, Moses doubted. God proved His power by having Moses throw down his shepherd's rod, which became a serpent, then picking it up restored it. When Moses worried Pharaoh would not believe, God told Moses and Aaron to do the same sign. Les teaches that these signs were not so much for Pharaoh's benefit but for Moses and Aaron, to prove God would do the supernatural and bring Israel out of Egypt. This pattern of supernatural signs continued throughout Israel's history and into Christ's earthly ministry, where Jesus performed miracles to prove to the Jew He was who He said He was, including seven miraculous signs in John.