This passage affirms Jesus' authority over nature (8:26), and if over nature, then over any crisis his followers may face. Many ancient accounts of nature miracles were purely legendary, but these generally surrounded characters of the distant past (compare R. Grant 1986:62) rather than arising when eyewitnesses remained. The tradition behind this particular story is very likely Palestinian, describing in traditional Galilean (contrary to foreign) fashion the Lake of Galilee as a "sea" (v. 24, literally, against the NIV; see Mk 4:39; see Theissen 1991:105-8).
Jesus' Ministry Exhausts Him (8:23-24)
Jesus' exhausted slumber in the boat passage incidentally illustrates his statement in verse 20 that the Son of Man has nowhere to lay his head. Perhaps as if to underline the point, Matthew omits Mark's mention of the makeshift cushion (Mk 4:38). Matthew also purposely emphasizes that Jesus' true disciples followed him (8:22-23).
Jesus Reproves the Disciples for Their Fear (8:25-26)
Jesus' peace (v. 24) contrasts starkly with the disciples' fear (v. 25); they are of little faith (v. 26), just like those who are anxious for tomorrow (6:30) or who doubt Jesus' power to work extraordinary miracles (14:31; 16:8; 17:20). Ability to sleep during trouble was often a sign of faith in God (Ps 3:5; 4:8), and the Greeks also praised philosophers who demonstrated consistency with their teaching by maintaining a serene attitude during a storm (Diog. Laert. 1.86; 2.71; 9.11.68). Just as Jesus demands that we express our love for God by trusting him for material provision (Mt 6:25-34), he demands that we trust him for safety. Our heavenly Father may not always protect us from earthly ills, but he will do with our lives what is best for us (10:29-31). By this point in the narrative the disciples appear without excuse for their unbelief, like Israel in the wilderness; "Jesus expects them to have taken charge of the storm themselves" (Rhoads and Michie 1982:90, 93).
Jesus' Power Reveals His Identity (8:27)
If the disciples thought the boat might sink with Jesus aboard, it was because they did not understand Jesus' identity. His power over the sea, however, forces them to grapple afresh with that question. Faith in Jesus' authority flows from conviction concerning his true identity (compare 8:8; 9:6).
Stories about nature miracles occasionally circulated in antiquity, usually either stories about deities (R. Grant 1986:62) or legends about heroes of the distant past (as in Diog. Laert. 8.2.59; Blackburn 1986:190; compare t. Ta`anit 2:13). Parallels to the Jonah story (Cope 1976:96-98) can link the disciples' amazement at Jesus' stilling of the storm to God's stilling the storm in the Jonah story (Jon 1:15-16); other backgrounds in the Hebrew Bible also point to Jesus' identity with God (see in Lane 1974:176). In biblical tradition it was God whom the seas obeyed (as in Job 38:8-11; Ps 65:5-8; 89:8-9; France 1985:162). The astonishment of Jesus' disciples is therefore understandable (Mk 4:41; 6:51)! Their cry for Jesus to save them reflects one sense of the Greek term save ("deliver safely") but probably also alludes on a literary level to Jesus' broader mission (Mt 1:21).