ISB ~ 1 John 4 v2

come in the flesh:The most serious denial of the false teachers (2 Jn 7). John makes several emphatic assertions about the physical reality of Jesus’ humanity to counter this rejection (1 Jn 1:1-2; 4:14; 5:6-8; Jn 1:14). Denial of the Incarnation of Christ took many forms in Christian antiquity (CCC 465). See introduction to 1 John: Purpose.