Romans 10:13: “Everyone who calls on the name of Jehovah will be saved” (Rom. 10:13 NWT).
10:13 cannot be disconnected from verse 9 in that the same “Lord” in verse 9 is the same Lord in verse 13 (from Joel 2:32) calling upon Christ as YHWH.
JW are taught that the term “Jehovah” is the *true* name of God (see, The term “Jehovah” and the JWs).
Further, they assert that the term “Jehovah” was actually removed from the original Greek NT and thus faithfully restored by the NWT. Except, of course, when the OT passages is referring to Jesus Christ, they do not follow their own rule. For example, the phrase “Jesus as Lord” in Romans 10:9 is clearly the antecedent to the occurrences of the pronoun “Him” and “Lord” following up to verse 13:
9 that if you confess with your mouth ‘Jesus as Lord’ [Κύριον Ἰησοῦν], believe in your heart that God raised Him from the dead, you will be saved;
10 for with the heart a person believes, resulting in righteousness, and with the mouth he confesses, resulting in salvation.
11 For the Scripture says, “WHOEVER BELIEVES IN HIM WILL NOT BE DISAPPOINTED.”
12 For there is no distinction between Jew and Greek; for the same Lord is Lord of all, abounding in riches for all who call on Him;
13 For “WHOEVER WILL CALL ON THE NAME OF THE LORD [YHWH] WILL BE SAVED” (cf. Joel 2:32).
“Jesus as Lord” is the object of salvation from verse 9-13. Throughout these passages, it is the same “Him” and same “Lord” beginning in verse 9. To say that the “Lord” in verse 9 is a different “Lord” than in verse 13 completely breaks the flow of the passages. The Lord that one confesses (v. 9) is the same Lord that one calls upon for salvation (v. 13). In verse 13, Paul cites Joel 2:32: “whoever calls on the name of the Lord [Heb. YHWH] will be delivered.” Thus, whoever confessing and calls upon Jesus as Lord, that is, Jesus as YHWH will be saved.
In fact, there are many places where the NT authors cite OT passages referring to YHWH and apply them to Jesus Christ. This is a great way to share the truth about Jesus to JWs. For example, compare Psalm 102:25-27 with Hebrews 1:10-12; Isaiah 6:1-10 with John 12:39-41; Isaiah 8:12-13 with 1 Peter 3:14-15; Isaiah 45:23 with Philippians 2:10-11; Joel 2:32 with Romans 10:13. The most productive way to use this witnessing tactic is to first take the JW to the OT passage first, then have him read the NT passage where the author cites the OT passage and applies it to Jesus.
In v. 9, Jesus is called “Lord.” And from vv. 9-13, all pronouns refer grammatically to Jesus (i.e., “Him” in vv. 9, 11, 13, and 13 refer to the closest named person: “Jesus”).
Therefore, Paul in v. 13 sees Jesus as the Yahweh of Joel 2:32 (“whoever calls on the name of the LORD [YHWH] will be delivered”; NASB) whereby those confessing Jesus as YHWH will be saved (cf. v. 9).
When using this way of showing that Jesus is the “Jehovah” of the OT (distinct from the Father, though) have the JW read the OT passage first. Then, after agreeing that “Jehovah” is being referred to, have he or she read the NT passage in which the NT author applies the OT passage to Christ Jesus.