In Likutei Moharan II, 46, Rebbe Nachman says that the word KaShYA – a “difficulty” or “question” – consists of the initial letters of the verse “Sh’ma Y-K-V-K Koli Ekra: Hear, Hashem, my voice – I cry….” (T’hillim 27:7).
Reb Natan adds:
This lesson teaches that when we cry out with our heart, this itself is an aspect of emuna (faith). We may have many questions and grave doubts, G-d forbid, but when our heart cries out, it shows that we still have the burning spark of emuna. Without this spark, we would remain still. Therefore, the cry itself is in the category of emuna. Understand this. (Sichot HaRan #146)