Lord
שמע ישראל יהוה אלהינו יהוה אחד
Hear, O Israel! Yahweh our God, Yahweh is one.
Deuteronomy 6:4
"Jesus is Lord." If you read that sentence and your mind jumped to Jesus being lord of a person's life, or to His kingship, then you may be desensitized to the force of certain biblical language. That sentence meant "Jesus is Yahweh," and stronger language than that is in the New Testament.
The connection between "Lord" and "Yahweh" may not be obvious to the modern reader. The covenant name of God, Yahweh, had been revealed to Moses as a memorial for all generations [Exod 3:15]. Its misuse was prohibited by the Third Commandment [Exod 20:7]. But by the first century, even mispronouncing The Name was viewed as irreverence, so it was neither spoken nor transliterated. In speech, people substituted the Hebrew word Adonai, meaning "My Lord." The Shema [Deut 6:4] would have been recited "Adonai Elohenu," not "Yahweh Elohenu." This meant that, to the Jews of Jesus's day reciting the holiest confession of Judaism, "Lord" was the closest approximation to the actual name of God, not the more generic word "God." Once one understands this, the full significance of declarations like 1 Corinthians 8:6 may be understood.
Yahweh
The lord who breaks through, בַ֫עַל פְרָצִים ⇒ First Chr 14:11
(David named a victorious battle site this phrase, because Elohim—the lord who breaks through his enemies like water bursts out—was the One who accomplished it through David).
Lord of Heaven and Earth, אֲדוֹן כָל־הָאָ֫רֶץ ⇒ Josh 3:11; 3:13.
The Father
The Lord, (ὁ) κύριος ⇒ [6x] Acts 4:26; 4:29; 7:33; 2 Tim 1:16, 1:18 (1st usage); 2:19 (1st usage).
The Lord of Lords, κύριος τῶν κυριευόντων ⇒ 1 Tim 6:15.
Lord of Heaven and Earth, οὐρανοῦ καὶ γῆς κύριος ⇒ Acts 17:24.
The Son
The lord of King David ⇒ [5x] Ps 110:1; Matt 22:44; Mark 12:36; Luke 20:42; Acts 2:34.
Lord of the Living and the Dead, νεκρῶν καὶ ζώντων κυριεύσῃ ⇒ Rom 14:9.
The Lord Jesus (middle markedness at minimum; possibly = to YHWH) ⇒ [6x]
Acts 15:11 (ὁ κύριος Ἰησοῦς); 15:26 (ὁ κύριος ἡμῶν Ἰησοῦς Χριστός); 16:31 (as the sole requirement for salvation, not "God"); 19:13 (Jewish exorcists tried to name the name of the Lord in abjuration); 19:17 (the name of The Lord Jesus was magnified by Ephesian believers after Jewish exorcists could not prevail merely by naming the name of Jesus); 20:35 (Lord Jesus, remember the words of).
Lord ≈ Yahweh ⇒ [22x]
Luke 1:16; 1:17; 1:43; 1:68; 1:76; John 20:28b; Acts 9:17; 19:5; 21:13; 21:14; Rom 10:9; 10:12; 1 Cor 1:2; 1:8b; 8:6c; 12:3; Eph 4:5; Phil 2:11b; 3:20; Jude 1:4; 1:14; Rev 22:5c.
The Lord of All, ὁ κύριος πάντων ⇒ [2x] Rom 10:12; Acts 10:36.
One Lord, εἷς κύριος ⇒ [2x] 1 Cor 8:6; Eph 4:5.
Our Only Lord, ὁ μόνος κύριος ἡμῶν ⇒ Jude 1:4.
"My Lord and My God," ὁ κύριός μου καὶ ὁ θεός μου ⇒ John 20:28.
The Spirit
The Spirit of the Lord, τὸ πνεῦμα κυρίου ⇒ Acts 5:9.
Lord ≈ Yahweh [3x] ⇒ 2 Cor 3:17; 3:18; 2 Tim 2:7.
2 Cor 3:17 ⇒ The Spirit is The Lord, ὁ κύριος τὸ πνεῦμά ἐστιν ≈ "The Spirit is
Yahweh."
2 Cor 3:18 ⇒ The Lord Spirit, κύριος πνεῦμα ≈ "Yahweh Spirit" » God The Spirit.
So who is The Lord? The Father or The Son or The Spirit? The answer is "yes."