Isaiah 29:24 promises wayward will gain understanding — the same transformation as 32:4's fearful heart learning to know.

Isaiah 35:5 expands the healing motif: the blind see and deaf hear—parallel to stammering tongues speaking clearly in the messianic age.

Isaiah 35:6 also promises the mute's tongue sings—directly echoing the stammerers speaking fluently in 32:4.

Luke 21:15 promises a mouth and wisdom from God, the same divine enabling of speech that turns stammerers into plain speakers here.

Matthew 12:22 shows Jesus healing a mute man—fulfilling the promise that stammerers would speak clearly (Isa 32:4).

Mark 7:35 describes a man's tongue released to speak plainly—directly echoing Isaiah's stammerers speaking clearly.

Exodus 4:11 affirms God's sovereignty over speech, the same divine power that enables stammerers to speak plainly in this prophecy.

Matthew 11:25 reveals truth to the childlike — echoing 32:4's assurance that the humble fearful heart will understand.

Matthew 16:17 attributes Peter's understanding to divine revelation — fulfilling 32:4's promise that hearts will know through God.