As per the Prajapita Brahmakumaris, nature must go through a period of phased degradation starting from sattva, rajas and finally to tamas.
Tamas is associated with inauspiciousness, breakdown of values, degradation of nature and human beings, destructive conficts and war.
Rajas is associated with egoism, activity, desires, passion.
Sattva is associated with pure consciousness, harmony, auspiciousness, happiness and bliss.
The present kali yuga or Iron Age is predominant in tamas while the earlier Golden Ages, Silver Age were predominant in sattva, and the bronze age was predominant in rajas.
This is the reason why the present age seems to be anarchic and chaotic, due to the predominance of the inauspicious tamas.
Through meditation, remembrance of God and cultivation of divine virtues, we can increase the auspicious sattva around us, and reduce the inauspicious tamas.
Hence it is not God, but the phased degradation of nature corresponding with decline in moral values in human beings that is the cause of evil.
You can find more information in this article by Anthony Strano, Director of Brahmakumaris in Greece.
Time and Transformation - About Brahma Kumaris
Brahma Kumaris - Original and Official website