Both evil and good occur within the permissive providence of God. The only real evil occurs when sin is committed, thus upsetting the moral order. In sin, there is the absence of a good that should be present. As such, the only real and absolute evil is sin, which is mysteriously linked to suffering, but not necessarily as cause and effect. Sin and suffering are linked.
Evil is therefore the absence of what ought to be there.
10 God's providence is mysteriously, inexorably bound up with evil. 12 Holiness, which would not be possible were it not for Christ's redemptive suffering, is derived from patient endurance of pain and suffering. Thanks to Christ's redemptive work we are now able to imitate the suffering Christ and cooperate in our own salvation. To suffer means to carry a cross. It is some trial or pain endured whose efficient cause is the fall of Adam.