David Wilkerson emphasizes that spending time with Jesus transforms believers into His likeness, instilling purity, holiness, and love, which in turn fosters a boldness for God. He illustrates this through the example of Peter and John, who, despite facing intimidation from religious leaders, stood confidently in their faith after healing a crippled beggar. The boldness they exhibited was rooted in their identity in Christ, allowing them to speak fearlessly before their accusers. Wilkerson highlights that true spiritual authority comes from being filled with the Holy Spirit and having a clear conscience in Christ. This boldness is a reflection of the righteousness believers possess through their relationship with Jesus.