The Lord Jesus, before His ascension, said "… ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth" (Acts 1:8 ). That means you have the self-generating power to effect changes, and be an effective witness for the Lord Jesus. This power works like a dynamo in you and it’s by the operation of the Holy Spirit.
The Master also described the operation of the power of the Holy Spirit in the Christian as "... rivers of living water" (John 7:38). There’s something "bubbling" inside us, propelling us to minister the Word of God with power, and dispense His goodness. The presence of the Holy Spirit, not just with us, but in us, makes us effective witnesses of the resurrection. We just can’t keep quiet about the Gospel; it’s like fire shut up in our bones (Jeremiah 20:9).
The Church of Jesus Christ is not weak and powerless, as the devil would want to make us believe; we’re empowered witnesses. We’re anointed to preach the Gospel, "…not with wisdom of words, lest the cross of Christ should be made of none effect" (1 Corinthians 1:17), but in the demonstration of the Spirit, and of power (1 Corinthians 2:4). The cross of Christ wouldn’t be effective in our day if our preaching comes only with words. Christianity is a supernatural life and the power of God must be demonstrated in our lives, and we must impact the world with the same power. Anything short of this isn’t true Christianity.
Keep walking in the light of God’s Word, and be conscious of the reality of the Holy Spirit who lives in you, and has endued you with power to be an effective witness.