The mendicant year has two halves. For eight months monks and nuns practise vihara: walking barefoot from place to place, never staying more than a few days in one town, sleeping in lodgings lent by laypeople, and covering long distances — Jain monastics do not use vehicles of any kind, which means an acharya may walk thousands of kilometres over a career and cannot leave India. During the four months of the monsoon they stop, because saturated ground teems with insects and germinating life and walking on it is unavoidable himsa. This is chaturmas, and it structures Jain religious life: the concentration of preaching, scriptural recitation, lay vow-taking and festivals into the rainy season is a direct consequence, and Paryushana falls inside it. Towns compete to secure a well-known acharya for their chaturmas, and the arrival is a significant local event. The rule against vehicles is also why Jain teaching abroad has depended on lay teachers and, in the Terapanth case, on the specially created samani rank, who are permitted to travel.