The following proud boast comes from The Second Helvetic Confession (Chapter IX; Of Free will):
MAN DOES EVIL BY HIS OWN FREE WILL. Therefore, in regard
to evil or sin, man is not forced by God or by the devil but does evil by his
own free will, and in this respect he has a most free will. But when we
frequently see that the worst crimes and designs of men are prevented by God
from reaching their purpose, this does not take away man's freedom in doing
evil, but God by his own power prevents what man freely planned otherwise. Thus
Joseph's brothers freely determined to get rid of him, but they were unable to
do it because something else seemed good to the counsel of God.
Let us focus on that lofty boast from the Confession asserting that "Man does evil by his own free will." Man does NOT do evil by his own free will. In regard to evil or sin, man is NOT forced or tempted by God (James 1:13-14), but IS actively hardened and emboldened by God:
"And Sihon the king of Heshbon was not willing to let us pass by him, for Jehovah your God had hardened his spirit, and had emboldened his heart, so as to give him into your hand, as [it is] this day" (Deuteronomy 2:30).
God did NOT force Sihon to sin; God did NOT tempt Sihon to sin (cf. James 1:13-14). Rather God HARDENED Sihon's spirit and EMBOLDENED his heart to do what God defined as evil in order that He might destroy king Sihon along with "men and women and little ones."
"And Jehovah said to me, Behold, I have begun to give Sihon and his land before you; begin to possess, in order to possess his land. And Sihon came out to meet us, he and all his people, to battle at Jahaz. And Jehovah our God delivered him before us, and we struck him and his sons, and all his people. And we captured all his cities at that time, and utterly destroyed every city, men and women and little ones. We did not leave a remnant" (Deuteronomy 2:31-34).
To those with even a modicum of reading comprehension must realize that king Sihon was not doing evil by his own free will.
These comments regarding the issue of "free will" are well put:
"Right. The issue of 'free will' in Calvinism has mainly focused on the doctrine of Total Depravity. In the doctrine of Total Depravity, those who are totally depraved do not have the free will to choose to do good. But there is another issue of 'free will,' and that relates to totally depraved man’s ability to freely choose to do any kind of evil, to freely choose between different wicked thoughts, actions, and words. In this area of free will, most Calvinists deny God’s sovereignty."