why Jesus allegedly said "But those mine enemies, which would not that I should reign over them, bring hither, and slay them before me"
We have Hebrews 2:14-15 >
"Inasmuch then as the children have partaken of flesh and blood, He likewise shared in the same, that through death He might destroy him who had the power of death, that is, the devil, and release them who through fear of death were all their lifetime subject to bondage." (Hebrews 2:14-15)
So, I see here how Jesus is all about love. Jesus so superior even has shared "in flesh and blood" with us. And Jesus is so unconceited that Jesus God's own Son suffered and died like He did, on the cross of Calvary, so He could save us and share God's very own good with us.
By the way > Jesus knows about hell; part of why Jesus suffered like that is He knows how hell is, and so He considered it worthwhile to suffer that much in order to make sure we don't go there.
And the fact that Satan had people doing all that cruelly hateful stuff to Jesus is evidence of how horrible Satan and his evil spirit is, and how humans acting in Satan's spirit can do things. There is "the spirit who now works in the sons of disobedience" (in Ephesians 2:2). And there are people who have been living in this spirit > such Satanic people crucified Jesus. Even Jewish mommies and daddies called for the crucifixion of Jesus, crying out, "His blood be on us and on our children" (in Matthew 27:25); so Satan's evil and filthing spirit made even Jewish mothers and fathers so able to betray and curse even their own children and to so reject their own Messiah. And Satan's spirit in any of us could have brought any of us to do the same thing > our Apostle Paul, a Jew, is clear how "we all" have been "children of wrath, just as the others." (in Ephesians 2:3)
So, Jesus has come to save us from Satan and sin and the horrible spirit of sin. This spirit of selfishness has to go somewhere, and there are vessels for carrying it there. Romans 9:21 is clear how God has vessels for honor but also for dishonor. Satan's spirit is the spirit of "fear of death" (Hebrews 2:14-15), "the spirit of bondage" (Romans 8:15) to fearing death, also the spirit of being love-dead > Satan shares love-dead things with his people > "bitterness, wrath, anger, clamor, and evil speaking" and "malice" > see Ephesians 4:31.
So, I think it can be very clear why Jesus went through Calvary in order to destroy the devil. And God's love has not been enough to satisfy Satan and his people to become loving. So, fire will be needed to control such stubborn beings. And Jesus has done what we need. Humans with their weapons and Bible arguing and politics can not do all which Jesus has done and is doing, to move Satan and his spirit and human vessels of this filth to the flaming sewer which burns with fire and brimstone. In the news we are seeing how much humans have proven themselves able to do to stop Satan and his evil spirit in people. But evil and vessels containing it is all on its way to where God will keep it all!!
So, yes there is "the severity of God", our Apostle Paul does say in Romans 11:22. God is good and His mercy endures forever, but this includes how He is able to keep Satan and his evil spirit from messing us with unforgiveness and pride and dominating and dictatorial lusts for pleasure; and in God's peace through Jesus, there is almighty power to keep us from giving in to "fear of death" which makes people love-dead and easy to control with stubborn desires for money and pleasure and depending on the false security of military and materials, instead of depending on God.
@Godistruth1 > It is like how a mother grizzly bear can tenderly care for and warmly love her little cubs whom she keeps near her tummy, while at the same time she is smashing wolves who are trying to catch and kill and eat her baby cubs. She is so loving and can keep her cubs in peace, but she is severe against those wolves.
"For our God is a consuming fire." (Hebrews 12:29)
Fire now can burn Satan and his things away from us, while that same fire warms our hearts in His peace.
"Therefore submit to God. Resist the devil and he will flee from you." (James 4:7)