I have little doubt that for most people in the modern world, evil is defined in terms of inflicting suffering upon other people.
Modern attitudes to abortion and euthanasia suggest that the infliction of suffering is regarded as worse than killing*; and even the grossest harms of the transagenda - mutilation, poisoning, physical suffering of children - are 'justified' in terms of supposedly reducing mental suffering.
Christians - or at least, strongly self-identified Christians - have often felt the same way; despite whatever contrary lip-service they pay to Christ's Kingdom being "Not of this world".
As well as personal hopes, there has been a vast and complexly-abstract theology purporting to explain how this-world is to be "redeemed", re-made in ways that include the elimination of all suffering - or indeed assertions that the resurrection of Jesus Christ has actually already improved this world by ways including the reduction of suffering.
(i.e. The common Christian belief that there has been less suffering in the world because of Jesus than there would have been without Jesus; or that there has been less suffering in Christian societies than in non-Christian.)
The belief that suffering is the worst evil is certainly sincere, heartfelt - and indeed seems often to overwhelm people with an urgent craving for the elimination (or at least substantial reduction) of suffering in this world; or to overwhelm them with despair that this is no so, and that suffering continues.
So far as I can tell, the only answer to such a conviction, to this state of being overwhelmed by the horror of suffering that afflicts so many people; is to stay with the conviction and take it further, until you come out of the other side.
The only convincing answer is to imagine - as fully, realistically, and honestly as possible - what kind of a world there would be, or would Not be, if the elimination of suffering really were the primary value.
Because Not Being is, indeed, the destination of a morality that intends to eliminate suffering in this world, as this world is constituted - which is, a world in which entropy rules, and death will always eventually prevail.
How it is that the imperative of Not Suffering interacts with our actual mortal world to produce an ethic of Not Being, is something that each person needs to work-through for himself; because humans have an infinite capacity for resisting arguments they do not want to be true.
Nonetheless; such is the insight that awaits anyone who allows himself to step out-from that state of being overwhelmed, and either frenzied or paralyzed, by the pervasiveness of suffering.
I think that only then can we properly understand what Jesus Christ actually offered Mankind; which was not directed at this world, but at another.
Jesus is indeed reported as saying as-much, many times, in the Gospels; but that other-worldliness, that fulfilment in Heaven and only in Heaven, that Second Creation, needs to become the basis of our Christian understanding.
*This is true, even though the amount of evil is commonly measured in terms of dead bodies: e.g. the evil of Hitler or Lenin-Stalin is asserted or compared primarily in terms of the numbers of people they deliberately exterminated. Political power, nowadays, is mainly rooted in the authority to define whose suffering matters the most; because this suffering (and its purported alleviation) is the basis of most of the major leftist agendas such as socialism, feminism, prohomosexualism, the transagenda, and antiracism.