Acts 2:2 says, "And suddenly there came a sound from heaven, as of a rushing mighty wind, and it filled the whole house where they were sitting. Then there appeared to them divided tongues, as of fire, and one sat upon each of them."
WoW! How exciting would that be!! Although the Holy Spirit had visited various people in the Old Testament era, it had never been a permanent filling as it was on that day. From that day forward, each of us who are born again, are immediately -- and permanently -- filled with the Holy Spirit of God, and He has promised never to leave us. "Lo, I am with you always..." Matthew 28:20.
Although we tend to take it for granted, being filled with the Holy Spirit is a huge -- and I might add -- supernatural wonder that is the biggest blessing God gives us on this earth.
"May the God of hope fill you with all joy and peace in believing, so that by the power of the Holy Spirit you may abound in hope" Romans 15:13.