Yājñavalkya Śikṣā 46

46

yathā vāṇī tathā pāṇī riktaṃ tu parivarjayet
yatra yatra sthitā vāṇī pāṇistatraiva tiṣṭhati

As the speech is, so the hand should be; one should avoid an empty [hand]. / Wherever the speech is positioned, there indeed the hand remains.