“Sea of Galilee.” The “sea” of Galilee is actually quite a small lake, only 7 miles (11.2 km) across and 12 miles (19.3 km) long, and the entire lake can be seen from the escarpments on both the east and west sides. The Greek word thalasso, lake, sea, or ocean, does not really refer to the size of the body of water, and thus has to be translated into the English “lake,” “sea,” or “ocean” by knowing the body of water that is being referred to. Because the body of water is historically known as, and called, “the Sea of Galilee” we leave that name intact when its proper name is mentioned. However, when it is not referred to by name, we refer to it like it actually is—a lake. The “Sea of Galilee” is the only freshwater lake generally referred to as a “sea.” Technically, “seas” are saltwater.
“for they were fishermen.” In this case, Peter and Andrew were fishermen. There would be other people who used cast nets to catch fish to eat.
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