In ancient times people would often consider that large scale events or events that were out of their control were caused by "fate" or "heaven" or "the gods." When something important was going to happen that was outside of their control they would pray to the gods for help, much as people do today.  If things turned out badly they would ascribe it to the "will of heaven."  A soul being born into the world and the day of one's death seemed to be the type of events too significant to be the result of mere human accident and whim. When it says "the gods" I think that it is really a personification of "fate" or "destiny"  If a friend of yours has a death in the family you will feel like you should help by giving them an explanation to soothe their loss.  Still today, people will often explain someone's death by saying that "God took him (or her) home."  The quote is expressing the same idea, it is just that the identity of "the gods" has changed.  

Good explanation! I feel that we should replace the gods with God. 

Thanks buddies! I wanted to know others' opinion.

According to Wikipedia, that saying is a maxim by Menander, a Greek dramatist. The gods refers to the ancient Greek gods.