Faith is released by words. "By your words you will be acquitted, and by your words you will be condemned" (Mt 12:37). "The tongue has the power of life and death" (Pr 18:21). "The tongue of the wise brings healing" (12:18). Jesus taught "'out of the overflow of the heart the mouth speaks'" (Mt 12:34). The faith you have is expressed in speech. "What he says will happen" (Mk 11:23). It works because of the characteristics of the communication. Jesus said "the words I have spoken to you are spirit and they are life" (Jn 6:63). He also reveals "'I am in the Father . . . [and] the words I say to you are not just my own'" (14:10).
It has to be in accordance with God's words "in you" (Jn 15:7). The words are there if you meditate on the book of the law (Jos 1:8). They are there because "Your word I have treasured in my heart" (Ps 119:11). "From Your precepts I get understanding" (:104). "The unfolding of Your words gives light" (:130). "Your testimonies . . . are my counselors" (:24). "Jesus answered, 'It is written, 'Man shall not live on bread alone, but on every word that proceeds out of the mouth of God'" (Mt 4:4). He repeats it being written in verses 7 and 10. "If they speak not according to this word, it is because there is no light in them" (Isa 8:20).