Shiva Purana
जलाग्निब्राह्मणादीनां देवानां नाभिमुख्यतः । लिंगं पिधाय वामेन मुखमन्येन पाणिना ११ ।
He must never sit in front of water, fire, a brahmin or the idol of any god. He must screen the penis with the left hand and the mouth with the right.
english translation
jalAgnibrAhmaNAdInAM devAnAM nAbhimukhyataH । liMgaM pidhAya vAmena mukhamanyena pANinA 11 ।
hk transliteration by Sanscript