 But that's not the filling of the Holy Spirit. The sealing of the Holy Spirit in Ephesians 1.13 is different from the filling of the Holy Spirit. There are two different things. You are sealed with the Holy Spirit the moment you believe in the Lord Jesus Christ. But you are told in Ephesians 5.18 to be filled with the Holy Spirit. What is the difference? Well, you can lose the filling, but you never lose the sealing.