In the Old Testament the Sea of Galilee is known as the Sea of Kinnereth (Num.34:11; Josh. 12:3; 13:27), a name that is imaginatively associated with the Hebrew word kinnor meaning a harp. For some the lake is shaped like a harp, for others the music of its waters resembles the sound of a harp. Matthew and Mark call it the Sea of Galilee (Matt. 4:18; 15:29; Mark 1:16; 7:31) or simply the Sea (Mark 2:13 etc.) to which John adds the Sea of Tiberias (6:1; 21:1). Luke pedantically calls it the Lake (8:22) or the Lake of Gennesaret (5:1), a name which reflects the usage of Josephus who calls it the Lake of Gennesar because of the remarkable qualities of the region north of Tiberias.
The lake is 21 km from north to south and 12 km wide at its broadest point. The water-level fluctuates considerably, depending on the rainfall each year and on the quantity pumped from the lake which serves as the reservoir for the National Water Carrier; the mean level is 210 m below sea-level. The water is sweet, and in summer (when the temperature averages 33 C) too warm for a really refreshing swim. Twenty-two species of fish are found in the lake; fishing is again the important industry it was in the time of Jesus, and the small boats have still to watch for the sudden gusts from the surrounding wadis which can whip the normally tranquil surface to turmoil in a matter of minutes (Matt. 8:23-7; 14:24-33). The waves driven against one shore bounce back to collide with those coming in.
To relive the most beautiful pages of the Gospel and enjoy the memories which in a most delightful manner recall the familiar figure of Christ upon the waters of the Lake of Tiberias, one had best take a boat and sail, Gospel in hand, along its shores.
Source: The Holy Land by Jerome Murphy- O’Connor