The work of the Holy Spirit in John 3 is applied to the wind (the same word as spirit). From a human perspective, the wind has a point of origin and a destination that is unknown, yet we know the wind is present based upon the effects it leaves behind. Likewise, we are totally at the mercy of the free and sovereign will of God. Just as the wind is invisible and unpredictable and uncontrollable, God’s Spirit is moving among human beings, regenerating their hearts, and enabling them to willingly trust Christ for salvation. And when people do trust Christ, there will be evidence of His presence.