ISB ~ Matthew 14 v25

the fourth watch:The 12 hours of the night between 6 P.M. and 6 A.M. were divided into four “watches” (cf. Mk 13:35). This event took place between 3 and 6 A.M. and suggests the disciples were battling the storm most of the night.

walking on the sea: See note on Mt 8:27.