‘It has been stated that tongues plus interpretation equal prophecy. This is based on 1 Cor. 14:5, and is true. Why then is there such a thing as the gift of tongues when prophecy, in the plan of God, gives directly in one’s own language the message of the Spirit? The first answer is that which God has done is always well done, and it is not becoming of us to criticize God. isaiah prophesied by the Spirit, “For with stammering lips and another tongue will he speak ti this people.” Isa. 28:11, 12. Jesus Himself said, “And these signs shall follow them that believe; . . . they shall speak with new tongues.” Mark 16:17. Thus, tongues are God’s idea and operation, and they who criticize Him and His plan do so at their own peril.’
Source: Ralph M. Riggs, The Spirit Himself (1949), Chapter 22: Tongues and Interpretation of Tongues, p. 162.