The name of Jehovah does not appear in the NT because it was evidently removed by later copyists. That is evident by the fact that Jesus and the apostles frequently quoted from the Hebrew text where the YHWH appeared.
For example, when Jesus was tempted by the Devil three times, in each response Jesus quoted from the Jewish Law that contained the YHWH. It is inconceivable that when Jesus quoted from such texts containing the YHWH that he would not have pronounced his Father's name.
It does not undermine our confidence in God's Word that Jehovah-haters have always sought to erase or conceal the sacred Name of God. We know the Jewish scribes developed a superstition that forbade them from pronouncing the Name.
Likewise, modern translators have admitted to their bias in substituting LORD in the Hebrew text for the YHWH. It should come as no surprise that the early NT copyist were similarly over-reached by the Devil and influenced to erase God's name and replace it with LORD.
An abbreviated form of The Name does occur at Revelation 19:1, 3, 4, 6, in the expression "Alleluia" or "Hallelujah" in KJ, Dy, JB, AS, and RS.
The logic presented for the absence of the "full form" of the Divine Name in the NT had been that the inspired writers of the NT made their quotations from the Greek Septuagint version of the OT, which substituted Kyrios or Theos for the Tetragrammaton.
Commenting on the fact that the oldest fragments of the Greek Septuagintdo contain the divine name in its Hebrew form, Dr. P. Kahle says:
"We now know that the Greek Bible text [the Septuagint] as far as it was written by Jews for Jews did not translate the Divine name by kyrios; but the Tetragrammaton, written with Hebrew or Greek letters, was retained in such MSS [manuscripts]. It was the Christians who replaced the Tetragrammaton by kyrios, when the divine name written in Hebrew letters was not understood any more." (The Cairo Geniza, Oxford, 1959, p. 222)
When did Greek translators of O T stop using The Divine Name?
... evidently in the centuries following the death of Jesus and his apostles. In Aquila's Greek Version, dating from the second century C.E., the Tetragrammaton still appeared in Hebrew characters. Also, around 245 C.E., the noted scholar Origen produced his Hexapla, a six-column reproduction of the inspired Hebrew Scriptures:
"In Origen's Hexapla . . . the Greek versions of Aquila, Symmachus, and LXX [Septuagint], all represented JHWH by PIPI, in the second column of the Hexapla the Tetragrammaton was written in Hebrew characters." (The Journal of Theological Studies, Oxford, Vol. XLV, 1944, pp. 158, 159)
Why would the early copiests substitute kyrios (Lord) or theos (God) for The Divine Name?
From 66 CE to 135 CE there were:
Several Jewish revolts fostered much persecution by Roman authorities upon any who appeared Jewish;
After the apostle's deaths, there was a great falling away from the true faith. (2 Thessalonians 2:3; 2 Peter 2:3);
Most Jewish Christians were killed by the Roman authorities, leaving mostly "Gentile" Christians. These Gentile Christians wanted to appease the Roman authorities and gain approval amongst Romans, in general, and therefore may have developed a propensity to discard almost anything that made them look Jewish, including The Divine Name.
Greek philosophies were put on par with the Holy Scriptures. (2 Timothy 6:20, 21)
No matter how you break it down, God Almighty revealed His name thousands of years ago as YAHWEH (Exd 6:3 - Jehovah), and quite emphatically declared that His name would never, ever change (Ex.3:15).
Yahshua (Jesus) said that God was His Father, and clearly proclaimed God the Father's name as distinct from His own. Even through the closing chapters of Revelation, God the Father's name remains an identifying feature between God's people and others.
Though it is true that Yahshua (Jesus) is to be given a new name (Rev 3:12), it is equally true that God Almighty's name was, is, and always will be YAHWEH (English: Jehovah).
References: The Holy Bible.
Philippians 2:9 reads: "For this very reason also God exalted him to a superior position and kindly gave him the name that is above every [other] name, so that in the name of Jesus every knee should bend of those in heaven and those on earth and those under the ground, and every tongue should openly acknowledge that Jesus Christ is Lord to the glory of God the Father."
The context of Philippians reveals Jesus to be a humble and willing servant of God, who willingly forsook his privileged place in heaven and came to the earth and died a horrible death on a torture stake. That's why Paul said "for this very reason also God exalted him."
It does not matter which translation a person chooses to read, the truth is still obvious to those who are not bent on deception: God exalted Christ and gave him an honored name above all others.
What does the word "gave" mean to you?
It means that God granted Jesus the most honored place in the universe as a reward for his faithfulness. That is the simple truth. Christ Jesus did not exalt his own name. Jehovah did. Anything that distorts that precious truth is antichristian and from the Devil.