Genesis 18:12 Therefore Sarah laughed within herself, saying, after I am waxed old shall I have pleasure, my lord being old also?
So, what shall we take from this “physiologically incomprehensible” forecast from the angel visitors? Abraham had been promised to be the Father of Many Nations by God. Here we have the inside view of Sarah as she overheard the conversation of her husband and his heavenly messengers, one of which, I believe was Jesus, but that’s for another day. She laughed within herself, scripture says. As a woman, I can see where she was coming from. Her husband was 99 years old and she was not too far behind, probably 90 or 91, according to historic accounts. The problem here is Sarah’s unwillingness to believe God, hence, the laugh.