Q. I let Jehovah's Witness missionaries in my house today, and was thoroughly embarassed; I couldn't show them anything to substantiate that Jesus is Jehovah! I know Jesus is God--how do I show the next Witness at my door?
A. You can show a Witness any scripture, and no matter how clear, you must remember: Witnesses are trained to interpret all Scripture in the light of the Watchtower's literature, all of which is unscholarly, and definitely unscriptural.
Jehovah's Witnesses Answered Verse by Verse (Reed), and For Jehovah's Witnesses 'Who Love The Truth' (Cetnar-an amazing compilation of Watchtower materials), are excellent resources which show "Jehovah's organization" to be a false prophet, basing an earthly salvation on a false hope.
The most important thing to tell a Jehovah's Witness is that Jesus is Jehovah. This is not difficult to prove using either your Bible or the Witnesses' New World Translation. With all other issues, use your Bible. The NWT is untrustworthy.
Dealing solely with the question "Is Jesus Jehovah?", have the Witness go through Romans 10:9-13 with you.
"Open to Romans 10, verse 9," you say. "What does your New World Translation say?"
"Publicly declare that Jesus is Lord and believe in your heart that he was raised from the dead, and you will be saved," the Witness reads.
"Whose name are you calling on for salvation?"
Meet the moment of silence with your next point.
"Ok, verse 10," you continue. "Read that out loud, please."
The Witness begins,"With the mouth one makes public declaration for salvation."
"What public declaration?" you ask.
"That Jesus is Lord," the Witness answers.
"Right! Continue reading verse 11."
"None that rests his faith on him will be disappointed," the Witness replies.
"Who is him? The subject of verse 9 and 10, right?"
"Jesus!" the Witness will whisper.
"Right! Read verse 12!"
"Our Lord, rish to those calling on him."
The Witness begins to catch on. "Verse 9 says we are to call on Jesus!"
"By name! That's right! Please go on! Read verse 13!"
"For everyone who calls on the name of Jehovah will be saved."
"Good, now go back to verse 9. Whose name do we call on to be saved?"
"You got it!"
This passage is merely Paul explaining that Jesus is GOd based on OT verses about God (Joel 2:32) applied directly to Jesus. Verses 9 and 13 are references to the same profession that saves, precisely that Jesus is Lord. Verse 13 is identifying the same one to call on for salvation that is named in verse 9.
Other impacting verses: Ephesians 1:21; Acts 4:12; and Philippians 2:9.
Wherever "Jesus" and "worship" are mentioned together, the NWT replaces "worship" with "obesiance," which is defined by the Watchtower as "prostrating oneself before a god." God then to Exodus 34:12-15, where Jehovah commands His people not to prostrate themselves before other gods. If, in fact, Jesus is another god or God, then paying Jesus obesiance is defying Jehovah's command. But Jehovah has said that every knee shall bend at the name of Jesus (Philippians 2:9-11). Since there is no other God (Isaiah 45:5,22), and all other gods (like Baal, Dagon, Satan, Herod) are false, the only conclusion would be that Jesus is Jehovah!