XXXI. Hence it is moreover clearly evident, that neither voice nor singing, if used in prayer, has any validity, or produces the least benefit with God, unless it proceed from the inmost desire of the heart. But they rather provoke his wrath against us, if they be only emitted from the lips and throat; since that is an abuse of his sacred name, and a derision of his majesty; as we conclude from the words of Isaiah, which, though their meaning be more extensive, contain also a reproof of this offence: “The Lord said, Forasmuch as this people draw near me with their mouth, and with their lips do honour me, but have removed their heart far from me, and their fear toward me is taught by the precept of men,—therefore, behold, I will proceed to do a marvellous work among this people, even a marvellous work and a wonder; for the wisdom of their wise men shall perish, and the understanding of their prudent men shall be hid.”[395] Nor do we here condemn the use of the voice, or singing, but rather highly recommend them, provided they accompany the affection of the heart. For they exercise the mind in Divine meditation, and fix the attention of the heart; which by its lubricity and versatility is easily relaxed and distracted to a variety of objects, unless it be supported by various helps. Besides, as the glory of God ought in some respect to be manifested in every part of our bodies, to this service, both in singing and in speaking, it becomes us especially to addict and devote our tongues, which were created for the express purpose of declaring and celebrating the Divine praises. Nevertheless the principal use of the tongue is in the public prayers which are made in the congregations of believers; the design of which is, that with one common voice, and as it were with the same mouth, we may all at once proclaim the glory of God, whom we worship in one spirit and with the same faith; and this is publicly done, that all interchangeably, each one of his brother, may receive the confession of faith, and be invited and stimulated by his example.