Shomrai HaBrit is not responsibe for the links that tripod placed above.. they are highly inappropriate and we have emailed support. We continue to await their reply

The missionaries will say that Isaiah 48:16 shows that the "Trinity" is found in the Tanach, which they call the "Old Testament."

The Reply is: The verse says "Draw near to Me and hear this: from the beginning, I did not speak in secret; from the time anything existed, I was there. "And now the L-rd G-d has sent me, [the prophet Isaiah] endowed with His spirit [i.e. the spirit of prophecy, a gift]." If you read the 2 verses above this one, you will see that the chapter is dealing with Cyrus as G-d's instrament. G-d has planned this from the beginning, and is now implementing his plan. There is nothing in this verse that says anything about Jesus or the "Trinity". The "Trinity" is, in fact, an idea alien to the entire Tanach.