The story of Jesus walking on the water seems to allude to much Old Testament imagery. God treads the waters (Job 9:8; 38:16; Ps 77:19; Isa 43:16; 51:10; Hab 3:15). Jesus passing by the disciples sounds similar to Old Testament epiphanies (Exod 33:19-34:16; 1 Kgs 19:11-12).
Moreover, Jesus encouragement to the frightened disciples, “Fear not. I am. Don’t be afraid,” beckons us to several Old Testament passages (Exod 3:18; Joel 2:9; Isa 43:2).
As Jesus walks on the water, the disciples are seeing the covenant God of Israel, who passes by His people, and is present with them in the waters.