George Fifield (1859 – 1926) was an Adventist pastor who gave a series of sermons in 1897 showing that, even at that time, there was an understanding of a non-violent God. It seems that, over the decades since, this knowledge was to a considerable degree lost and is only quite recently again becoming more prominent.
Read his three sermons here:
Sermon 1, Feb. 9, 1897 on Isaiah 53:3
Sermon 2, Feb. 10, 1897 on Hebrews 9:22, Christian Consecration
Sermon 3, Feb. 11, 1897 on John 12:24-25, Die to Live
George Fifield also wrote book titled God is Love (1897) which you can download at the link.