Your problem is that you can only conceive of obedience in terms of following the letters of the law of Moses. GOD said to obey his voice. GOD's voice is living and not static letters engraved in stone or written in a book. GOD also said that after Moses he would send a prophet speaking in his name. Jesus didn't give 10 commandments; he gave two - love GOD and love mankind. He is the one we are to listen to and obey.
You are absolutely right, God said to obey His voice. Moses was chosen to 'hear His voice" because the people were frightened when they heard the voice of God. So Moses recorded God's Words. His Word is His voice. Ministers, preachers and teachers are sometimes His voice. Jesus is His voice and His Words are recorded. The question is "was Jesus the God of the Old Testament"? I believe He was and that He is also God with us. The problem you have seems to be that you believe Moses spoke on his own and that the recorded Words in the Torah are not God's Words. This is our major dividing line. But I will share more of His Word and how I know that I know that I know His voice.
God said we learn precept by precept and line upon line, right?
Isa 28:9 Whom shall he teach knowledge? and whom shall he make to understand doctrine? them that are weaned from the milk, and drawn from the breasts.
Isa 28:10 For precept must be upon precept, precept upon precept; line upon line, line upon line; here a little, and there a little:
Isa 28:11 For with stammering lips and another tongue will he speak to this people.
Isa 28:12 To whom he said, This is the rest wherewith ye may cause the weary to rest; and this is the refreshing: yet they would not hear.
Isa 28:13 But the word of the LORD was unto them precept upon precept, precept upon precept; line upon line, line upon line; here a little, and there a little; that they might go, and fall backward, and be broken, and snared, and taken.
The Entire Bible is God's Word. The Entire Bible is still applicable today in our lives. It is in maturity that saints have "ears that hear" and "eyes that see".
Jesus said "John 10:11
I am the good shepherd: the good shepherd giveth his life for the sheep."
And John 10:14
"I am the good shepherd, and know my sheep, and am known of mine."
Joh 10:15 As the Father knoweth me, even so know I the Father: and I lay down my life for the sheep.
Joh 10:16 And other sheep I have, which are not of this fold: them also I must bring, and they shall hear my voice; and there shall be one fold, and one shepherd.
Mat 10:6
But go rather to the lost sheep of the house of Israel.
Mat 15:24 But he answered and said,
I am not sent but unto the lost sheep of the house of Israel.
Hear, O Israel
Deuteronomy 5:1 And Moses called all Israel, and said unto them,
Hear, O Israel, the statutes and judgments which I speak in your ears this day, that ye may learn them, and keep, and do them.
Deuteronomy 6:4
Hear, O Israel: The LORD our God is one LORD: Deu 6:5 And thou shalt love the LORD thy God with all thine heart, and with all thy soul, and with all thy might.
Deu 6:6 And these words, which I command thee this day,
shall be in thine heart:
And Jesus quotes the scriptures Mark 12:29-31:
Mark 12:29 And Jesus answered him, The first of all the commandments is, Hear, O Israel; The Lord our God is one Lord:
Mar 12:30 And thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind, and with all thy strength: this is the first commandment.
Mar 12:31 And the second is like, namely this, Thou shalt love thy neighbour as thyself. There is none other commandment greater than these.
In the "Old Testament" there are over a 100 scriptures relating to how to love and interact with your NEIGHBOUR. Just saying, I believe Jesus simplified the lengthy code, because they all knew the scriptures (scriptures being the Tanach/Old Testament) and there was no need to quote every one of them. Kind of like this: Joh 20:30 And many other signs truly did Jesus in the presence of his disciples, which are not written in this book:
Joh 20:31 But these are written, that ye might believe that Jesus is the Christ, the Son of God; and that believing ye might have life through his name.
Joh 10:25 Jesus answered them, I told you, and ye believed not: the works that I do in my Father's name, they bear witness of me.
Joh 10:26 But ye believe not, because ye are not of my sheep, as I said unto you.
Joh 10:27 My sheep hear my voice, and I know them, and they follow me:
Joh 10:28 And I give unto them eternal life; and they shall never perish, neither shall any man pluck them out of my hand.
Joh 10:29 My Father, which gave them me, is greater than all; and no man is able to pluck them out of my Father's hand.
Joh 10:30 I and my Father are one.
Matthew 11:5 The blind receive their sight, and the lame walk, the lepers are cleansed, and the deaf hear, the dead are raised up, and the poor have the gospel preached to them.
Luke 7:22 Then Jesus answering said unto them, Go your way, and tell John what things ye have seen and heard; how that the blind see, the lame walk, the lepers are cleansed, the deaf hear, the dead are raised, to the poor the gospel is preached.
Look up each of these:
Matthew 11:15 He that hath ears to hear, let him hear.
Matthew 13:9 Who hath ears to hear, let him hear.
Matthew 13:43 Then shall the righteous shine forth as the sun in the kingdom of their Father. Who hath ears to hear, let him hear.
Mark 4:9 And he said unto them, He that hath ears to hear, let him hear.
Mark 4:23 If any man have ears to hear, let him hear.
Mark 7:16 If any man have ears to hear, let him hear.
Luke 8:8 And other fell on good ground, and sprang up, and bare fruit an hundredfold. And when he had said these things, he cried, He that hath ears to hear, let him hear.
Luke 14:35 It is neither fit for the land, nor yet for the dunghill; but men cast it out. He that hath ears to hear, let him hear.
I don't believe you are hearing the voice of the Good Shepherd, yet. Act 5:29 Then Peter and the other apostles answered and said, We ought to obey God rather than men.
Deu 4:30 When thou art in tribulation, and all these things are come upon thee, even in the latter days, if thou turn to the LORD thy God, and shalt be obedient unto his voice;
Deu 4:31 (For the LORD thy God is a merciful God
he will not forsake thee, neither destroy thee, nor forget the covenant of thy fathers which he sware unto them.
Deu 4:32 For ask now of the days that are past, which were before thee, since the day that God created man upon the earth, and ask from the one side of heaven unto the other, whether there hath been any such thing as this great thing is, or hath been heard like it?
Deu 4:33 Did ever people hear the voice of God speaking out of the midst of the fire, as thou hast heard, and live?
I don't know about you, but I have never heard the audible voice of God, but our ancestors did and all His Words are recorded for us today in the scriptures.
The problem, as I understand it, there is no dispensation of Israel and the Church being two separate entities being dealth with differently. That is an inherited lie from our fathers and the prophet Jeremiah spoke God's Words and it has been recorded for us today. Jer 16:19 O LORD, my strength, and my fortress, and my refuge in the day of affliction, the Gentiles shall come unto thee from the ends of the earth, and shall say, Surely our fathers have inherited lies, vanity, and things wherein there is no profit.
Jesus did not change the Sabbath to Sunday or all days of the week. That is another inherited lie from our fathers.
Heb 13:8 Jesus Christ the same yesterday, and to day, and for ever.
Proverbs 24:21 My son, fear thou the LORD and the king: and meddle not with them that are given to change:
Malachi 3:6 For I am the LORD, I change not; therefore
ye sons of Jacob are not consumed.
I've stated it before, but worth stating again, Deu 29:12 That thou shouldest enter into covenant with the LORD thy God, and into his oath, which the LORD thy God maketh with thee this day:
Deu 29:13 That he may establish thee to day for a people unto himself, and that he may be unto thee a God, as he hath said unto thee, and as he hath sworn unto thy fathers, to Abraham, to Isaac, and to Jacob.
Deu 29:14 Neither with you only do I make this covenant and this oath;
Deu 29:15 But with him that standeth here with us this day before the LORD our God,
and also with him that is not here with us this day:
So do you agree HEROSEFROMTHEDEAD that you believe that God changed and Jesus changed God's covenant to include omitting the fourth commandment?