I think to allow a witness to the salvation of Paul who once was a persecutor but now is in Christ. Ananias was the witness an contact into the local body of Christ in Damascus. Ananias argued because this man was the fiercest persecutor of the Church at the time and his life he thought would be in danger. It does take courage and boldness to trust in the Lord in the midst of seemingly dangerous circumstances.
Ananias is faithful to the message he received and was a witness of the indwelling of Paul by the Holy Spirit.
Yes God has guided me to speak for Him on many occasions, just happenstances that occur in the normal circumstances of life.
