Wow this is intriguing,speaking in tongues is so important to the believer,the primary way to pray in the new convenant is in tongues,and when we pray in tongues we generate power to effect change and work signs,wonders and miracles.Acts 1:8 But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth.
And also we build up ourself and most holy faith,you can't enjoy the fullness of the new creation without speaking in tongues.Jude 1:20 But ye, beloved, building up yourselves on your most holy faith, praying in the Holy Ghost.