Mark 11:23-24 are the "go to" verses for most anyone teaching faith. In these verses, Jesus promises that anyone who speaks to a mountain, telling it to move without doubting that it will, will see the mountain move. In another place, Jesus says that if we speak to a sychamine tree and command it to throw itself into the sea, it will obey us, if we do not doubt the power of our words. Now, I must ask the question, does God want us to go around moving mountains and trees? I don't think so, but obviously, there are some things that should be moved.
In Jude 20-21 Jude tells us to build ourselves up on our most holy faith by praying in tongues. Is this a mountain that should be moved? Is it important for believers in Jesus to stay built up in their faith? I believe the answer is an unequivocal "yes!" In Mark 11:24 Jesus pointed out the importance of faith being verbalized. Again, if we use my translation, what we believe must be verbalized. Therefore, we might set aside some time to build ourselves up on our holy faith by praying or speaking in tongues, but before we do, we should verbalize our intention.
Similarly, Jude tells us we can keep ourselves in God's love by speaking in tongues. Leaving aside the arguments over whether you can get out of God's love, doesn't it make sense that this is a mountain we should seek to move? Therefore, verbalizing faith concerning the gift of tongues' ability to keep us surrounded by God's love makes perfect sense.
In Romans 8:26, Paul informs us that we can pray about things we don't know about or don't have God's guidance on how to pray by yielding to the wisdom the Holy Spirit possesses. Though we might just let the rivers flow, wouldn't it seem to be wisdom to speak out our faith concerning the Holy Spirit's willingness to help first? Jesus said, "if you are going to move mountains or even just trees, you are going to have to tell them what you want them to do."
Although it might seem ludicrous to believe that we have the power to direct the Holy Spirit, is that not what Jesus said in Matthew 16:18, "I will give the keys to the kingdom of heaven to you", and again in Matthew 18:18, "whatever you loose, I will loose"? If we want to move this present darkness swirling around us, all we have to do is release the Light. Jesus is the light of the world, represented in the earth by the Holy Spirit. We can release the Light into the world, by releasing the Holy Spirit out of our bellies, but this act is most effective when we release Him by a direct act of our will, in faith, believing what God has said. We need to act in the authority Jesus gave us, in all humility and love, for although it seems clear we have the authority to release the Holy Spirit into the earth, He remains God Almighty.
It seems perfectly obvious to me that the principals of faith apply directly to the use of the gift of tongues. I expect that I could spend three whole days teaching on the gift of tongues without covering the same ground twice. Such is the wealth of information contained in the scripture. Beyond the scriptural references are the many experiences I have had with the Holy Spirit, which add understanding to the foundation of the Word of God. These two truths are integral to each other, but apart from hearing the truth of God's Word, we cannot have faith to believe on it.