I remained faithful to my aquatic guru. Under his watchful eye I lay on the beach and fluttered my legs and scratched away at the sand with my hands, turning my head at every stroke to breathe. I must have looked like a child throwing a peculiar, slow-motion tantrum. In the water, as he held me on the surface, I tried my best to swim. It was much more difficult than on land. (1.3.7)
Don't forget, on a practical level, how important Pi's swimming lessons are. If Pi never learned to swim, his survival wouldn't have happened. We're not saying that Pi's survival, on a more allegorical level, doesn't have to do with faith or a journey of faith. The lifeboat, Richard Parker, and the ocean all test Pi's faith. Or, put another way, they test his ability to swim in a foreign element.