Jesus does not have His own will to tell men to do (Mat 7:21). Why would men do? Hence, Mark 7:7.

Jesus makes it clear that His commandments are not from Him (Matthew 7:21, John 8:28) but are the will of God Our Father who is in charge. God The Father put Jesus in charge and gives Jesus the power to do it all (Luke 10:22). 

To those of us to whom Jesus reveals Himself and God the Father, we understand the hierarchy in the monotheistic Godhead from the teachings of Jesus who is YHWH because it is written, among other declarations, that we are taught by God (John 6:45) but who defers to the unknown God the Father Whom only Jesus made known to us (John 17:6-8, 25-26) and Who Jesus says is greater than Him (John 10:29, 14:28). Since His revelation, we come to understand the plural connotation of the phrase 'let us make man'. Because Jesus has made known God the Father to us, critical thinking skill makes us also understand that the exceedingly popular and well-known worldwide YHWH cannot be the formerly unknown God the Father (Malachi 1:11-14).

Jesus (God) is very eloquent in preaching and teaching us; however, Jesus says that it is God the Father who draws us to Jesus (John 6:44) because flesh and blood cannot draw us to Jesus to discover who He is (Matthew 16:17). Jesus says that many are called but few are chosen (Matthew 22:14) because even though we are drawn to Him by God the Father we must listen to Him (Genesis 49:10) not to the One who draws us to Him because the Father does not directly do the talking to any dead sinner (Genesis 2:16-17, 3:3) but His Son does (John 3:16) the teaching to save man by implementing the plan of salvation of God the Father (John 3:16). As such, none of us may think of bypassing or ignoring Jesus to go to God the Father, whether we have been revealed God the Father or not (Luke 10:22, Jon 7:28-29, John 14:6). YHWH God is YHWH God because He obeys (John 4:25, 8:28, Luke 2:11, John 1:49, 1 Samuel 8:7, 19-22).

Note that John 14:6 does not make YHWH God the God the Father of Jesus because YHWH God was all over humankind before the Advent of Jesus, because He took the form of man to hang out with Abraham, because He spoke to Moses from the burning bush, because He spoke to the Israelites at Sinai, and because Moses saw His back. YHWH would have even shown Moses His face if His Face would not kill the man who would see it. YHWH God is unseen not invisible. YHWH God was too close to men for now to require that Jesus dies and becomes the Mediator, the Reconciliatory Advocate between Him and man.

We know that Jesus does not have His own agenda (John 7:16, 8:29) nor his own will because He says He speaks according to what God the Father taught Him and that when we reject His word, we are indeed rejecting the word of the God the Father who sent us to Him (John 8:39-59, 14:14).

If Jesus only speaks of what God the Father have taught Him to tell men to do to inherit eternal life, how can any man engage in teaching his own precepts to other men to engage with God when no man has ever communicated with God the Father? Because even Jesus may not make the rules for men to follow to stay the death verdict in the garden of Eden, no man may assume that authority which belongs only to God the Father. That is why Jesus forbids in Mark 7:7 those of us who follow after Him to teach or to follow any of the precepts of men in matters of belief or faith, an act of disobedience that annuls our worship or makes our worship vain, void, pointless.

Who is man to seek to change, by any plausible pretense, the Saturday Sabbath day of God (Jesus) into Sunday? Who is man to decree that Saturday is no longer the Sabbath day, but Sunday is the Christian sabbath arguing plausibly that it is the resurrection day of YHWH (Jesus)? According to the manuscripts, Jesus was not even risen on a Sunday but on the first of the sabbaths (Mathew 28:1 YLT, LITV). Who is man to ordain the celebration of the birth of Jesus and the resurrection of Jesus? When did God the Father communicate those religious revelations to men as new observances?

God the Father only teaches His will to YHWH God (Jesus) who, in turn, teaches it to Moses who teaches to us. In the book of Apocalypse, God the Father communicated the details of the end of the world to Jesus (YHWH) who sent His Messenger to reveal it to John who reveals it to us.

The revelation for salvation according to the sanctioned behavior and belief or faith in the Law of Moses had been closed since Sinai according to Deuteronomy 4:2, et cetera. 

Not every one who says to me, Lord, Lord, shall enter into the kingdom of the heavens, but he that does the will of my Father who is in the heavens.  Matthew 7:21 Darby

No one can come to me unless the Father—the One who sent me—draws him. And I will raise him up on the Last Day.  John 6:44 CJB

John 6:44-46 CLV

(44) No one can come to Me if ever the Father Who sends Me should not be drawing him. And I shall be raising him in the last day.
(45) It is written in the prophets: And they shall all be taught of God. Everyone, then, who hears from the Father and is learning the truth, is coming to Me."
(46) Not that the Father has been seen by anyone, except by the One Who is from God. This One has seen the Father."

John 17:25-26 LITV
(25)  Righteous Father, indeed the world did not know You, but I knew You; and these have known that You sent Me.
(26)  And I made known to them Your name, and will make it known, that the love with which You loved Me may be in them, and I in them.

Matthew 16:17 ASV
(17)  And Jesus answered and said unto him, Blessed art thou, Simon Bar-Jonah: for flesh and blood hath not revealed it unto thee, but my Father who is in heaven.

John 14:6 ASV
(6)  Jesus saith unto him, I am the way, and the truth, and the life: no one cometh unto the Father, but by me.

John 8:28 LITV
(28)  Then Jesus said to them, When you lift up the Son of Man, then you will know that I AM; and from Myself I do nothing; but as My Father taught Me, these things I speak.