Vocal prayer must be accompanied by reflection. A prayer in which a person is not aware of to Whom he is speaking, what he is asking, who it is who is asking and of Whom, I don't call prayer... no matter how much the lips may move.
St. Teresa of Jesus

..."vocal" prayer is not to be understood as simply saying words. If the mere words of a prayer alone are said without the soul's raising itself to God, this is only an outward show and not real prayer. The designated words, however, support the spirit and prescribe to it a fixed path.
~St. Teresa Benedicta of the Cross from Love for Love