Ezekiel 34:30 (ESV) … “And they shall know that I am the Lord their God with them, and that they, the house of Israel, are my people, declares the Lord God.”
The precise expression ‘a new covenant’ is one that is actually used only by Jeremiah (in a text quoted twice in Hebrews), which has unfortunately led many people to the misunderstanding that Jeremiah alone prophesied about a new covenant at all. But as can be seen very clearly here, Ezekiel also envisaged the future of Israel in terms of a renewal of the covenant, as did Isaiah.29 The most fundamental formulation of the covenant relationship is to be found in the reciprocal phrases ‘the Lord [Yahweh] is your God’ and ‘you [Israel] are his people’. Here, Ezekiel rather cleverly splits them in two, putting the first phrase in with the promise of a new David (24), and the second after the details of the blessings to come (30), before rounding off with an echo of both in the ‘shepherd and flock’ imagery (31).
So often Ezekiel had uttered the words ‘Then they will know that I am Yahweh’ in contexts of predicted judgment. What a relief and a joy it must have been to utter them again here (31), not with such negative implications, but rather with the wonderful thought that people would truly know the reality of God’s character as Yahweh when they live within the perfectly restored relationship of humanity and creation to him. They will not only know that Yahweh is God, but that he is with them (30)—no longer ‘against them’, no longer an enemy. For they too can now be described, no longer as ‘the house of rebellion’, but by their true covenantal title, the house of Israel.
The shepherd knows his sheep and they will know him. Yet again, we can clearly see the scriptural source of Jesus’ rich imagery for his own enduring and secure relationship to us, his flock.
 Wright, C. J. H. (2001). The Message of Ezekiel: A New Heart and a New Spirit. (A. Motyer & D. Tidball, Eds.) (pp. 282–283). Nottingham, England: Inter-Varsity Press.