Nope! Being one of God's sheep is CONDITIONAL on BELIEVING and FOLLOWING God's WORD. Those who are not God's Sheep do not hear His Voice as shown in the CONTEXT you leave out...
JOHN 10:1-4 [1], Truly, truly, I say to you, He that enters not by the door into the sheepfold, but climbs up some other way, the same is a thief and a robber. [2], But he that enters in by the door is the shepherd of the sheep. [3], To him the porter opens; and THE SHEEP (believers) HEAR HIS VOICE (the Word of God): and he calls his own sheep by name and leads them out. [4], And when he puts forth his own sheep, he goes before them, and THE SHEEP FOLLOW HIM: for THEY HEAR HIS VOICE (the Word).
JOHN 10:26-28 [26], But YOU BELIEVE NOT (unbelievers), BECAUSE YOU ARE NOT OF MY SHEEP (believers), as I said to you.
Note: Those who BELIEVE are God's SHEEP while those who DO NOT BELIEVE are NOT God's Sheep.
[27], MY SHEEP (believers) HEAR MY VOICE (the Word of God), and I know them, and THEY FOLLOW ME: [28], And I give to THEM (believers) ETERNAL LIFE; and they shall never perish, neither shall any man pluck them out of my hand.
NEED MORE SCRIPTURE?
MATTHEW 10:38 And HE THAT TAKES NOT HIS CROSS AND FOLLOWS ME IS NOT WORTHY OF ME.
JOHN 8:12 Then spoke Jesus again to them, saying, I am the light of the world: HE THAT FOLLOWS ME shall not walk in darkness, but shall have the light of life.
MATTHEW 4:20-22 [20] And THEY (those disciples who believed) straightway left their nets, and FOLLOWED HIM. [21], And going on from there, he saw other two brothers, James the son of Zebedee, and John his brother, in a ship with Zebedee their father, mending their nets; and HE CALLED THEM. [22], And they immediately left the ship and their father, and FOLLOWED HIM.
MATTHEW 19:27-28 [27], Then answered Peter and said to him, Behold, WE HAVE FORSAKEN ALL AND FOLLOWED YOU; what shall we have, therefore? [28], And Jesus said to them, Truly I say to you, That you which have FOLLOWED ME, in the regeneration when the Son of man shall sit in the throne of his glory, you also shall sit on twelve thrones, judging the twelve tribes of Israel.
JOHN 10:1-4 [1], Truly, truly, I say to you, He that enters not by the door into the sheepfold, but climbs up some other way, the same is a thief and a robber. [2], But he that enters in by the door is the shepherd of the sheep. [3], To him the porter opens; and THE SHEEP (believers) HEAR HIS VOICE (the Word of God): and he calls his own sheep by name and leads them out. [4], And when he puts forth his own sheep, he goes before them, and THE SHEEP FOLLOW HIM: for THEY HEAR HIS VOICE (the Word).
JOHN 10:26-28 [26], But you believe not (unbelievers), because you are not of my sheep (believers), as I said to you. [27], My sheep (believers) hear my voice (the Word of God), and I know them, and THEY FOLLOW ME: [28], And I give to them (believers) eternal life; and they shall never perish, neither shall any man pluck them out of my hand.
Those who have saving faith believe and follow God’s Word.