Yes, a faithful witness does not lie! As simple as such that an authentic witness provides a direct and straightforward statement. Such could usually have an impact on spiritual instruction in it. Jesus called His followers to be His witnesses (Acts 1:8). One of the fundamental obligations of a witness is, to tell the truth,  and to not lie. When we have true faith and understanding in the person and work of Jesus Christ, we can give a simple, faithful witness to Him. That’s it!!!