a. "Spiritual Poverty," such harsh words. I prefer "Intentional Self Induced Filing of Spiritual Bankruptcy." The literal emptying yourself of all desire to exercise personal self-will and to have renounced all preconceived opinions in a wholehearted search for God.
Willingly setting aside your present habits of thought, present views and prejudices, your present way of life if necessary; to eject, in fact, anything and everything that can stand in the way of your finding God.
We tend to reject God because we have great possessions, not unlike the Rich Young Ruler who missed one of the great opportunities of history, and "turned away sorrowful because he had great possession." Our great possessions (not necessarily always money) being preconceived ideas, confidence in our own judgment, ideas with which we happen to be familiar; spiritual pride born of academic distinction; sentimental or material attachment to institutions and organizations; life habits we have no desire to renounce; concern about human respect or fear of public ridicule...or maybe just being heavily invested in worldly honor and distinction.
"Intentional Self Induced Filing of Spiritual Bankruptcy" frees us from these possessions that keep us chained to the rock of suffering that is our exile from God.
b. Mourning and sorrow is not in itself a good thing...the Will of God is that everyone should experience happiness and joyous success. Jesus said, "I am come that they might have life, and that they might have it more abundantly." But...trouble and suffering are often useful, because most people will not bother to learn the Truth until driven to do so by sorrow and failure. Mourning and sorrow then become a relatively good things.
c. There is really no need for a Christian to have trouble which results in mourning. He always has the choice of learning by spiritual unfoldment (the WORD and PRAYER) or by painful experience, and it is his own fault if he makes the latter choice.
This general principle applies to every one of our difficulties as heirs of flesh. Our understanding that if we seek first the Kingdom of God and His Righteousness (His way of Doing and Being) typically comes after mourning over trouble, and sin. So our remorse can be a blessing in disguise in that we will be comforted or be able to experience the Presence of God, which is the end of all mourning.