I'm very happy I enrolled in Spanish language in adult evening class years ago. These four years come in very handy when I go to Spain, be it on a regular holiday or on a Camino.
The months before I'm off again , I try to read as many Spanish internet newspapers or watch the Spanish TV ( documentaries are ideal ) as possible to " train " my vocabulary and pronunciation.
Even though my conversations in Spanish only cover the basics ( but who wants to talk politics etc on the Camino anyway
) I notice that the Spaniards really appreciate my intentions.
People will be more forthcoming, invite you more easily to sit with them at their table, open that closed churchdoor for you etc...
I was also relieved to be able to express myself in a clear way in Spanish when visiting the Centro de Salud for a minor ailment and afterwards when I had to get a prescription at the pharmacy.
On the lesser travelled Camino del Ebro especially my basic Spanish came in very handy. No other pilgrim, except one man from Venezuela, so if I wanted to talk to someone it had to be with a Spaniard.
On the Frances I even got an unexpected discount at a hostal because I helped out the landlady translating between some French and German pilgrims.
And to finish : learning a new language is just fun. Certainly broadened my horzion.