“And take not the word of truth utterly out of my mouth, for my hope is in your rules.”
It is very easy when persecution comes to deny the truth. As a result, David here prays that he would remain steadfast in not only believing, but saying that he believes outwardly. This first and foremost must be the case in our prayer life. We need to pray and we need to not despair and simply listen to ourselves. Silence in terms of our communication with God reveals unbelief. Prayer shows that our hope is in Him and His rules.