The missionaries will say that in Exodus 17:15 Moses built an alter and named it, 'The L-RD is my Banner.' This verse "proves" that all the verses in Isaiah refering to a banner or signal or standard, which the missionaries say mean the Messiah, are also refering to G-d. They conclude, therefore, that G-d is the Messiah.
The Reply is: This is logically flawed. Moses named an alter, is Jesus an alter built by Moses? No. Banner has no messianic conotations whatsoever. Any questions?