The first folding knives date to the Iron Age 500 or 600 BCE approximately.
The spike on these knives would probably only be useful for breaking knots in twine or the blade for cutting a plug of tobacco.
Certainly, more than one was brought back from the Far East by sailors and used in a different way than originally intended. Many of these had the body that held the stylus and knife made from Ivory, thus making them even more desirable to own.
Wikipedia has a large section on the use of these tools.
https://en.wikipedia.org/wiki/Palm-leaf_manuscript