As we all know Luke Skywalker used the Force to destroy the Death Star in Star Wars: A New Hope.
Darth Vader famously says
The Force is strong with this one.
Yet three years later in The Empire Strikes Back, when he meets Master Yoda for the first time he appears to sense nothing of the Force in the great master, even though he feels:
... like we're being watched!
Initial, and (deceptively?) light-hearted encounter with Master Yoda