JEHOVAH is both a singular person and a singular God

 Genesis ch.6:6ASV"Wherefore say unto the children of Israel, I am JEHOVAH, and I will bring you out from under the burdens of the Egyptians, and I will rid you out of their bondage, and I will redeem you with an outstretched arm, and with great judgments:

I (first person SINGULAR) He is both the supreme person and the supreme God.

Exodus ch.18:11ASV"Now I know that Jehovah is greater than all gods; yea, in the thing wherein they dealt proudly against them." 

Deuteronomy ch.3:24ASV"O Lord JEHOVAH, THOU hast begun to show thy servant THY greatness, and THY strong hand: for what god is there in heaven or in earth, that can do according to THY works, and according to THY mighty acts?"

He is always address in singular personal pronouns for a reason

Deuteronomy ch.6:10ASV"And it shall be, when JEHOVAH thy God shall bring thee into the land which HE sware unto thy fathers, to Abraham, to Isaac, and to Jacob, to give thee, great and goodly cities, which thou buildest not,"

1Samuel ch.12:17ASV"Is it not wheat harvest to-day? I will call unto JEHOVAH, that HE may send thunder and rain; and ye shall know and see that your wickedness is great, which ye have done in the sight of JEHOVAH, in asking you a king."

2Samuel ch.7:22ASV"Wherefore THOU art great, O JEHOVAH God: for there is none like THEE, neither is there any God besides THEE, according to all that we have heard with our ears." 

JEHOVAH is both the greatest person and the greatest God.

1Chronicles ch.16:25ASV"For great is JEHOVAH, and greatly to be praised: He also is to be feared above all gods."

Psalms ch 83:18ASV"That they may know that [d]THOU ALONE, whose name is JEHOVAH,

Art the Most High over all the earth."

The name JEHOVAH is not Just another name as some disrespectfully claim it is the only name deservedly and exclusively borne by the greatest person in all of reality and is the only name ever described as Holy in all of scripture. It occurs more frequently in the bible than the the next five most common names/titles combined.

JEHOVAH Has the greatest zeal for his name.

Malachi ch.1:11ASV "For from the rising of the sun even unto the going down of the same my name [j]shall be great among the Gentiles; and in every place [k]incense [l]shall be offered unto my name, and a pure offering: for my name [m]shall be great among the Gentiles, saith JEHOVAH of hosts."

But who is this Greatest person who worthily bears this hallowed and greatest of names.

Luke ch.1:32ASV"He shall be great, and shall be called the Son of the Most High: and the LORD God shall give unto him the throne of his father David: "

The God and Father of Jesus Christ is the most high GOD. Logically if there are two other people who are as great as the God and Father of Jesus he is simply not the most high. The God And Father of Jesus is the lone owner of the sacred name,the Lord JEHOVAH.