‘From henceforth’, that is, from the time that Christ’s baptism of suffering and redemption are accomplished on Calvary’s cross, there will be a new order prevailing over the people of God, and with that new order will come divisions which were not apparent before. These divisions are not all against all; they are not personal divisions, as if each individual was against every other individual, and there was widespread general hostility.
We see by this the enormity of the change that the gospel brings about in a life. God calls on us to love him above all else, and that is entirely right. While the day of grace continues however, we love all, including our enemies, and we earnestly desire them to enjoy the same salvation we have been given, but if they will not come to Christ, eventually there will have to be a final parting.