The following test case shows two Text nodes with the three first letters in the Hebrew alphabet. The first node incorrectly shows the characters rendered from left-to-right (though not mirrored).

The second node consists of two lines, and this node displays both lines correctly.

See attached image.

import javafx.application.*;
import javafx.scene.*;
import javafx.scene.layout.*;
import javafx.scene.text.*;
import javafx.stage.*;

public class Hebrew extends Application {

    public static void main(String[] args) { launch(args); }

    @Override public void start(Stage stage) {
        VBox rootNode = new VBox(10);
        rootNode.setStyle("-fx-padding: 20;");

        Text text = new Text();
        text.setText("\u05D0\u05D1\u05D2"); // alef bet gibel
        rootNode.getChildren().add(text);

        text = new Text();
        text.setText("\u05D0\u05D1\u05D2\n\u05D0\u05D1\u05D2"); // Two lines
        rootNode.getChildren().add(text);

        Scene scene = new Scene(rootNode);
        stage.setScene(scene);
        stage.show();
    }
}