Thoughts are Real

 Why does the Torah tell us that after giving birth, a mother must bring a sin offering?

Rabbi Simon bar Yohai answers, "Since she may have cried out in the midst of her birthing pains, "I will never again let my husband come near me."
For such a thought, the Torah requires that a sin offering be brought.
Two ideas emerge from this passage. The first is that people are prone to say regrettable things. We will cry out in the depth or pain despair uttering curses or vows that, given a moment of rational thought, we would never say. The second notion is that even though all humanity may succumb to such wrong and excessive language; we are not excused from what comes from our mouths. We are always held responsible for what we say.
 
The Mishna in Pirkay Avot states, “Know what is above from you. An eye that sees, an ear that hears, and all of your deeds are recorded in a book! (2:1)