He shall judge between the nations, And rebuke many people; They shall beat their swords into plowshares, And their spears into pruning hooks; Nation shall not lift up sword against nation, Neither shall they learn war any more. (Isa 2:4 NKJ)
“The wolf also shall dwell with the lamb, The leopard shall lie down with the young goat, The calf and the young lion and the fatling together; And a little child shall lead them. The cow and the bear shall graze; Their young ones shall lie down together; And the lion shall eat straw like the ox. The nursing child shall play by the cobra’s hole, And the weaned child shall put his hand in the viper’s den. They shall not hurt nor destroy in all My holy mountain, For the earth shall be full of the knowledge of the LORD As the waters cover the sea. (Isa 11:6-9 NKJ)
The Bible doesn’t disagree with itself. The Old Testament has certain passages of Jewish eschatology that Jews all through the ages would have been looking for. According to Jewish tradition, the Messianic Era will be one of global peace and harmony, an era free of conflict and hardship, and one in which people will grow in their knowledge of Yahweh.
Paul’s teaching to the Church was going to be based on the theology of his Jewish roots, nothing different. As a Jew, he saw Jesus as a partial fulfillment of his Jewish eschatology and the remainder was still to come.