It would seem reasonable that people do not speak the name of God because of fear, but the commandment to fear God is coupled with swearing (truthfully) in His Name as the proper way to "fear God".

Thou shalt fear the LORD thy God, and serve him, and shalt swear by his name. Deuteronomy 6:13

and

And ye shall not swear by my name falsely, neither shalt thou profane the name of thy God: I am the LORD. Leviticus 19:12

In order for Yeshua to fulfill the law and the prophets and "fulfill all righteousness" (Matt 3:15), He would have sworn in His Father's name in obedience to the above commandments, even though He taught His disciples "do not swear at all" (Matt 5:34), as it was better not to swear, then to swear falsely. To swear in His Father's Name, He would have had to have spoken His Father's Name. I believe this is how the Sanhedrin convicted Yeshua of what they called "blasphemy", that He uttered the Divine Name.

And the high priest answered and said unto him, I adjure thee by the living God, that thou tell us whether thou be the Christ, the Son of God. Jesus saith unto him, Thou hast said: nevertheless I say unto you, Hereafter shall ye see the Son of man sitting on the right hand of power, and coming in the clouds of heaven.

I believe that when the text says "POWER", Yeshua spoke the name of His Father, resulting in the conviction, having HEARD what they considered "blasphemy", punishable with the utterance of the divine NAME.

Then the high priest rent his clothes, saying, He hath spoken blasphemy; what further need have we of witnesses? behold, now ye have heard his blasphemy. What think ye? They answered and said, He is guilty of death.

The Sanhedrin could not punish anyone whom they considered a "blasphemer" unless that person uttered the Divine name with his mouth along with what they deemed blasphemy.

The blasphemer is punished only if he utters the [Divine] Name. Tractate Sanhedrin 55b-56a

Of course, Yeshua did not blaspheme, nor did HE do anything wrong speaking His Father's Holy Name, the Name in which HE came. Yeshua did nothing worthy of death.

I believe that Stephen the Martyr also suffered death because he spoke the Divine Name. After completing his testimony, he concluded:

“Look,” he said, “I see heaven open and the Son of Man standing at the right hand of God.”

This idea of the "Son of Man" in the presence of God, is from the Book of Enoch:

There I beheld the Ancient of days, whose head was like white wool, and with him another, whose countenance resembled that of man. His countenance was full of grace, like [that of] one of the holy angels. Then I inquired of one of the angels, who went with me, and who showed me every secret thing, concerning this Son of man; who he was; whence he was and why he accompanied the Ancient of days. He answered and said to me, This is the Son of man, to whom righteousness belongs; with whom righteousness has dwelt; and who will reveal all the treasures of that which is concealed: for the Lord of spirits has chosen him; and his portion has surpassed all before the Lord of spirits in everlasting uprightness. 1 Enoch 46:1-2

When Stephen says "Son of Man standing at the right hand of God", they covered their ears... perhaps because of a certain NAME mentioned in place of "God". It would explain their reaction.

At this they covered their ears, cried out in a loud voice, and rushed together at him. They dragged him out of the city and began to stone him.

Their reaction of covering their ears is almost a superstitious response, as if what they heard was intolerable. They responded in a similar manner as the Sanhedrin, but with mob rule they took matters into their own hands. Perhaps they heard Stephen utter the NAME.

The blasphemer is punished only if he utters the [Divine] Name. Tractate Sanhedrin 55b-56a