What does “filled with the Holy Spirit” mean in the Bible?

For instance, in 1 Samuel 16:13, young David was filled with the Holy Spirit as he was anointed to be king. However, after the resurrection of Jesus, everyone who followed Christ and believed upon Him for salvation received and was sealed by the Holy Spirit until the day of redemption. (See Ephesians 1:13, 4:30, 2 Corinthians 1:22.) The first to receive the Holy Spirit after the resurrection of Jesus were the disciples. (See John 20:22). After salvation, the believer learns how to utilize the power of the Holy Spirit by learning to completely rely on the Holy Spirit for daily life as well as for specific tasks or service to the Lord. Paul instructs us in Galatians 5:25, “If we live in the Spirit, let us also walk in the Spirit.” When we learn to rely on the Spirit for daily life, we begin to express “the fruit of the Spirit” spoken of in Galatians 5:22-23. Daily reliance on the Holy Spirit creates a life of joy, peace, and contentment in all situations, as well as a deeper relationship with the Lord and a Christ-like character. It is this kind of relationship that allows the Holy Spirit to work mightily in one's life in service to the Lord, such as the work of the Holy Spirit in the disciples recorded in the Book of Acts. Yet, know this: we all have the same Holy Spirit! No believer has more than another just as no believer is more saved than another. (See 1 Corinthians 12:4,8-9,11.) Once saved. we must choose to live by the Holy Spirit. Romans 8:5 says, “For those who live according to the flesh set their minds on the things of the flesh, but those who live according to the Spirit, the things of the Spirit.” Therefore, set your mind on the things of the Spirit and learn to rely upon Him daily.