The Principle of Love and Desire By Ibn Taymiyyah

Shaykh-ul-Islaam Ibn Taymiyyah, was asked about the saying of the Prophet (sallallaahu ‘alayhi wa sallam) said, “The invocation of my brother Yunus: “None has the right to be worshipped save You; glory be to You, far removed are You from any imperfection; I have been amongst the wrong doers,” None who is experiencing difficulty employs it except that Allaah would relieve him of his difficulty.”

What is the meaning of this d’uaa?
Are their any unstated conditions that have to be met when one articulates it?
What is the connection between belief in the heart and the meaning of this supplication such that it leads to the removal of difficulty?
It is sufficient to acknowledge ones sin alone, or must this be accompanied by repentance and the firm resolve not to repeat that sin in the future?
Why is it that difficulty and harm is removed only when a person relinquishes any hope, reliance and dependancy upon the creation?
How can the heart relinquish the characteristic of putting hope in the creation and depending upon them, and instead put its hope in Allaah, Exalted is He, and turn to Him in its entirety?
What are the methods that would aid the heart in doing this?