Knock on wood
Janice Park first heard the phrase knock on wood during the winter of her freshman year in high school from a fellow student. It was during finals when everyone was getting sick except for her, and when she commented on this fact, her friend immediately told her to knock on wood so as not to jinx herself. She was told that by expressing her fortunate situation, she was exposing herself to bad luck. It would cause her to be jinxed and would quickly change her situation to a worse one. However, by knocking on wood, the jinx would become reversed and nothing bad would happen. Therefore, it is important to knock on wood when one exclaims good situations in order to avoid tempting fate.
It is often believed that boasting or expressing fortunate situations will encourage evil spirits to inflict damage on ones life. As it was once thought that spirits dwelled in the trunks of trees, it seemed fitting to people to knock on wood whenever a statement was made in order to prevent the spirits from hearing. By tapping on the wood, the spirit would not be able to hear the words being spoken and would therefore not be able to interfere in the individuals life. However, in modern days, knocking on wood has lost much of its historical connection with spirits. Rather, it is used now as a simple gesture that indicates hope for good luck to continue. Knocking on wood no longer prevents spirits from hearing peoples boastful comments but instead serves to appease the speakers nervous feelings for making such a statement.