The qualities of the Buddha as a teacher that led to the spread of Buddhism during his lifetime.
Actually Buddha's appearance was normal just like anyone else. How do we know?
However, in his prime, people were clearly attracted by the Buddha's physical good looks as much as they were by his pleasant personality and his Dharma. Just to be in his presence could have a noticeable effect upon people. That alone attracted many to his talks and they benefited from the teachings.
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