One of the many things I've grown to love about yoga is the language used in teaching it. Because yoga is largely ineffable, instructors resort to metaphor and simile and anecdote and allegory. And much of the historical literature is in the form of legends and aphorisms and sagas and poetry.
I know the New Age over- and undertones are offensive to some, and they were once to me too, but as a longtime practitioner, I've come to savor the lingo. "Open up your heart center" is a subtler instruction than "Stretch your pecs," and it feels different when you do it. Indeed, it's difficult to maintain a meanspirited, hateful, judgmental frame of mind—no matter how cranky you were when you unrolled your mat—when you are lifting and exposing your vulnerable beating heart. Unlike "Look up and cross your eyes," "Gaze into your third eye" makes you feel as if the spot between your eyebrows actually had the gift of sight. When you "breathe into the stretch," it feels, incredibly, as if air were being gently pumped into an area of tightness.
The names of the poses—the cat, the cow, the dog, the crow, the pigeon, the frog, the fish, the eagle, the peacock, the cobra, the tree, the hero, the warrior, the half-moon, the sun—are wonderfully evocative and down-to-earth at the same time. The silliness of the name "downward-facing dog," for example, lets some of the air out of yoga's holiness (as does sticking your bottom up). And consider the apt image of the tree, the name of a pose in which the feet root into the ground as the arms and hands reach skyward, swaying with the trunk to achieve balance. And of course, the corpse pose, the lazy woman's favorite, is just so ... corpselike.