Paraskaragrihyasutra 3.4.15

3.4.15

atha dakṣiṇato gopāyamānaṃ ca mārakṣamāṇā ca dakṣiṇato gopāyetāmityaharvai gopāyamānaṃ rātrī rakṣamāṇā te prapadye tābhyāṃ namo 'stu te mā dakṣiṇato gopāyetāmiti \15\

Then to the south: 'May that which protects and that which guards, protect me from the south.
'The Day is that which protects; the Night is that which guards; to them I apply; to them be adoration; may they protect me from the south.'