We had quite a few answers to the question we posed about the link between these two film stills. Most people identified the first film, but it was student Roger Berwick who was both first to answer correctly and who gave the best explanation.
The first image is from the dance scene in Jean-Luc Godard’s Bande à part.
Tarantino is a well-known cinephile, especially in international and low budget film making. He admires Godard’s work, but that is not the link between the two images. In the famous dance scene in Pulp Fiction, Tarantino didn’t want Thurman and Travolta to perform a well choreographed routine. He wanted them to be natural and fun and potentially awkward. So he showed the two actors the scene from Bande a part and told them that was what he wanted from them: naturalness and freedom and fun, despite being awkward and potentially out of time with each other. He wanted realism. Essentially, the performance in the first film was the inspiration for the performance in the second.