Peter's bold response to religious leaders in Acts 4 reveals a crucial truth: he was filled with the Holy Spirit. Being filled is different from being saved - we need regular refilling through prayer. When we operate spiritually dry, church becomes optional, we rarely speak about Jesus at home, and everything about God becomes convenient rather than essential. The religious leaders feared the name of Jesus because they understood its power. Prayer is the key to being filled with the Holy Spirit, not worship, tithing, or church attendance alone. When filled, even uneducated people display supernatural boldness and authority that comes from being with Jesus.