The most common pose of a Buddha that you will find in Thai temples, is him being seated with crossed legs, with the left hand in his lap, and the right hand touching the earth. This mudra is known as the "Earth Witness" mudra. According to legend, Prince Siddharta, after six years of meditating under a bodhi tree, was on the verge of reaching enlightenment. At that moment Mara arrived, the Demon of Illusions, and tried to dissuade Siddharta from his final steps to enlightenment. Siddharta meditated all night to overcome the fears and temptations sent by Mara. At that moment he called upon the Earth Goddess to witness his transformation and grant stability so he wouldn't cave into Mara's delusions. Witnessing that, the Earth Goddess made the ground shake and tremble and Mara's demons fled for good. And thus Prince Siddharta reached Enlightenment and became "the Buddha', the Fully Awakened One.