While a quote about faith I found it better applied to life. Your job, family, self.
It's easy to spend time in the shallow end of faith. It's not a real commitment. You can just hop in, stand around in tight circles, and people-watch. You can examine your nails, read, reread, and catch up on all the gossip. You can talk and talk and talk and come to a great many conclusions and decisions and still maintain your hairstyle and even avoid smudging your makeup.
I think the reason we don't hear from people in the deep end as often is because they're actually swimming. In the deep end, you have to keep moving. It's hard to look cool. It's tiring and scary even, since it's just you and your head and your heart in the silence of the depths. There's not much chatting or safety in numbers in the deep end. You have to spend most of your time there alone. And it's impossible to get any solid footing. You just have to trust that the water will hold you, and you have no their choice but to flail about and gasp for air and get soaking wet, head to toe.
Carry On, Warrior: Thoughts on Life Unarmed, page 204.