Kauṣītaki (Śāṅkhāyana) Brāhmaṇa 25.14.9

25.14.9

saṃvatsaram cared adhaḥ saṃveśya phāla kṛṣṭāśya pratigṛhṇan na annam yācann idam tat tad anuvasānaḥ.(.phāla kṛṣṭāśyaprati?) /

For a year he should wander, sleeping on the ground, eating [only food] ploughed by the share, accepting [what is offered], not begging for food, wearing whatever [clothing he obtains].