I have read through your study on God's will. I find it difficult to accept that God would willfully cause suffering in our lives.
Surely He would not willfully allow suffering, would He?
God’s main characteristic is His holiness. Yes, God loves (1 John 4:16) us, but we go ahead and sin anyway. We actually enjoy our sin. For example, our world promotes sexual sin as fun. Most men and women would agree that adultery looks like fun or is fun. God uses suffering to motivate us to not sin. God is more interested in our holiness than in our comfort. We do not really understand our Holy Creator. Listen to the following passage,
Know therefore today that it is the LORD your God who is crossing over before you as a consuming fire. He will destroy them and He will subdue them before you, so that you may drive them out and destroy them quickly, just as the LORD has spoken to you. “Do not say in your heart when the LORD your God has driven them out before you, ‘Because of my righteousness the LORD has brought me in to possess this land,’ but it is because of the wickedness of these nations that the LORD is dispossessing them before you. “It is not for your righteousness or for the uprightness of your heart that you are going to possess their land, but it is because of the wickedness of these nations that the LORD your God is driving them out before you, in order to confirm the oath which the LORD swore to your fathers, to Abraham, Isaac and Jacob. “Know, then, it is not because of your righteousness that the LORD your God is giving you this good land to possess, for you are a stubborn people. (NASB) Deuteronomy 9:3-6
In this passage, God makes it clear that He will destroy a nation because they sinned. In the following passage, God will discipline all parties because everyone sinned.
Then God sent an evil spirit between Abimelech and the men of Shechem; and the men of Shechem dealt treacherously with Abimelech, in order that the violence done to the seventy sons of Jerubbaal might come, and their blood might be laid on Abimelech their brother, who killed them, and on the men of Shechem, who strengthened his hands to kill his brothers. And the men of Shechem set men in ambush against him on the tops of the mountains, and they robbed all who might pass by them along the road; and it was told to Abimelech. (NASB) Judges 9:23-25
Few men or women have struggled against sin to the point of suffering. Most of us give in. So, God disciplines us. God has one goal in all of this. Listen,
You have not yet resisted to the point of shedding blood in your striving against sin; and you have forgotten the exhortation which is addressed to you as sons, “MY SON, DO NOT REGARD LIGHTLY THE DISCIPLINE OF THE LORD, NOR FAINT WHEN YOU ARE REPROVED BY HIM; FOR THOSE WHOM THE LORD LOVES HE DISCIPLINES, AND HE SCOURGES EVERY SON WHOM HE RECEIVES. It is for discipline that you endure; God deals with you as with sons; for what son is there whom his father does not discipline? But if you are without discipline, of which all have become partakers, then you are illegitimate children and not sons. Furthermore, we had earthly fathers to discipline us, and we respected them; shall we not much rather be subject to the Father of spirits, and live? For they disciplined us for a short time as seemed best to them, but He disciplines us for our good, that we may share His holiness. All discipline for the moment seems not to be joyful, but sorrowful; yet to those who have been trained by it, afterwards it yields the peaceful fruit of righteousness. (NASB) Hebrews 12:4-11
God desires our holiness more than he desires our comfort.
As obedient children, do not be conformed to the former lusts . . . but like the Holy One who called you, be holy yourselves also in all your behavior; because it is written, “YOU SHALL BE HOLY, FOR I AM HOLY.” (NASB) 1 Peter 1:14-16