Acts 10:42-44 ESV
42 And he commanded us to preach to the people and to testify that he is the one appointed by God to be judge of the living and the dead. 43 To him all the prophets bear witness that everyone who believes in him receives forgiveness of sins through his name. ”
44 While Peter was still saying these things, the Holy Spirit fell on all who heard the word.
Cornelius worshipped the Lord before he was given the Holy Spirit. Hearing the word, and upon believing the word, the Spirit came to him and his household.
As the Spirit descended upon Jesus upon His baptism in the water of the Jordon, so does the Spirit descend upon those who are washed in the word.