Today’s Catechism readings (243-248) describe the Holy Spirit as the “Paraclete” and “Advocate” sent by Jesus Christ. What do these two words mean?
“Paraclete” is the Greek word, and “advocate” is the Latin word, for this particular role of the Holy Spirit in our lives of faith. I happen to like etymologies (the study of the origin and development of words), because I find that knowing where a word comes from helps to understand the word more deeply.
“Advocate” comes from the preposition/prefix ad- (meaning “towards”) and vocate (from the verb vocare, “to call”). We get the word “vocal” from vocare.
“Paraclete” comes from the prefix para- (meaning “beside; near”) and clete (from the verb kalein, “to call”). We get the words “ecclesial” (church-related) and “epiclesis” (part of the Eucharistic Prayer) from the Greek verb kalein.
Both of these words, in Latin and Greek, mean “to call [someone] to [one’s] side.” An advocate or a paraclete is someone you call to yourself, often to speak for you. They are similar to intercessor (“one who goes” [cedere] “between” [inter-]).
This is why Jesus says He will send the Holy Spirit, because the Holy Spirit comes to our aid, comes to our side. The Holy Spirit is in the business of being close to us!