When You Pass Through the Waters - Sketch

Working on a digital piece for my dad and a teenage boy at his church who also has cancer. I'm trying to illustrate Isaiah 43:1-3, some of Dad's favourite verses at this time:

Do not fear, for I have redeemed you; I have called you by name; you are Mine! When you pass through the waters, I will be with you; and through the rivers, they will not overflow you. When you walk through the fire, you will not be scorched, nor will the flame burn you. For I am the LORD your God, the Holy One of Israel, your Savior.

Will be taking this into Illustrator to clean it up, then probably into Photoshop...I'd like to imitate a water-color effect with this, mostly because I know my parents will appreciate that style better =)

Thoughts and critiques are, as always, welcome.