The tradition also prescribes meticulousness in speech. As an example, we have the extensive, detailed instructions about the care we take in reciting the Sh'ma in the Talmud (BT Brachos 15). One of my acquaintances once said, we are so careful so that someone who over-hears us will getr it right. I would submit that Someone always hears our recitation. We always stand before the Kadosh baruch hu in our recitation. It is a sign of our love and respect for Him that we recite with care.
It says in Avos (3:1). Akavya ben Mahalalel said: Reflect upon three things and you will not come to sin. Know from where you came and where you are going and before whom you are destined to give account and reckoning. From where have you come?--from a putrid drop. Where are you going?--to the place of dust, worm, and maggot. Before whom are you destined to give account and reckoning?--before the supreme King of kings, the Holy One, blessed be he. ( http://www.pirkeiavos.org/) .