1. Etymology and Definition:The Hebrew word for king is melekh
; its denominative malakh, "to reign" "to be king." The word is apparently derived from the mlkh which denotes: (1) in the Arabic (the verb and the noun) it means "to possess," "to reign," inasmuch as the possessor is also "lord" and "ruler"; (2) in the Aramaic melekh), and Assyrian "counsel," and in the Syrian "to consult"; compare Latin, consul.
If, as has been suggested, the root idea of "king" is "counsellor" and not "ruler," then the rise of the kingly office and power would be due to intellectual superiority rather than to physical prowess. And since the first form of monarchy known was that of a "city-state," the office of king may have evolved from that of the chief "elder" or intellectual head of the clan.http://www.internationalstandardbible.com/M/molech-moloch.html
mo'-lek, mo'-lok (ha-molekh, always with the article, except in 1 Kings 11:7; Septuagint ho Moloch, sometimes also Molchom, Melchol; Vulgate (Jerome's Latin Bible, 390-405 A.D.) Moloch):
1. The Name
2. The Worship in Old Testament History
3. The Worship in the Prophets
4. Nature of the Worship
5. Origin and Extent of the Worship
1. The Name:The name of a heathen divinity
whose worship figures largely in the later history of the kingdom of Judah. As the national god of the Ammonites, he is known as "Milcom" (1 Kings 11:5,7), or "Malcam" ("Malcan" is an alternative reading in 2 Samuel 12:30-31; compare Jeremiah 49:1,3; Zephaniah 1:5, where the Revised Version margin reads "their king"). The use of basileus, and archon, as a translation of the name by the Septuagint suggests that it may have been originally the Hebrew word for "king," melekh. Molech is obtained from melekh by the substitution of the vowel points of Hebrew bosheth, signifying "shame."
From the obscure and difficult passage, Amos 5:26, the Revised Version (British and American) has removed "your Moloch" and given "your king," but Septuagint had here translated "Moloch," and from the Septuagint it found its way into the Acts (Amos 7:17), the only occurrence of the name in the New Testament.
Molech (signifies shame) derives from the hebrew word Melekh (king).
So your reference to David as Molech is incorrect. He is Melekh David not Molech David.