Don't Knock These Theories

A lot of people like to touch or knock on wood for luck,
In many different cultures; boy, the superstition’s stuck.
It may connect with pagan lore of spirits in the trees.
The knock would signal, “Lend us your protection if you please,”
Or drive off evil spirits lest they cause a tragic loss.
Some Christians would relate it to the wood of Jesus’ cross.
The other theory traces to a variant of tag
Where touching wood protected one from capture (what a drag).
This game of “Tiggy Touchwood” from the 19th century
Is backed by folklore scholars, so I think I should agree.