From a brief discussion in family devotions this morning.  First, the sheep of His hand:

Psalm 95:3-7a

3 For the LORD is a great God, and a great King above all gods.
4 In his hand are the deep places of the earth: the strength of the hills is his also.
5 The sea is his, and he made it: and his hands formed the dry land.
6 O come, let us worship and bow down: let us kneel before the LORD our maker.
7 For he is our God; and we are the people of his pasture, and the sheep of his hand.

John 10:27-29

27 My sheep hear my voice, and I know them, and they follow me:
28 And I give unto them eternal life; and they shall never perish, neither shall any man pluck them out of my hand.
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.

Second, hearing His voice:

John 10:27

My sheep hear my voice, and I know them, and they follow me:

Psalm 95:7b-8

7b To day if ye will hear his voice,
8 Harden not your heart, as in the provocation, and as in the day of temptation in the wilderness:

In John 10, our Lord’s reference to sheep in His hand would be striking for those who knew Psalm 95 and sang it regularly.  In that context, to speak of His sheep hearing His voice paralleled the psalm’s exhortation to hear the voice of the Lord.  But if anyone missed the implication of verse 27, He went on:

John 10:30

I and my Father are one.