"Samanthra" is an old hymn that comes from the 19th century shape-note hymn collection, Southern Harmony, first published in 1854 by William Walker.  It's a hauntingly beautiful melody that falls nicely out of the Aeolian minor mode that is derived from capo-ing at the 1st fret out of D-A-d tuning (key of Em).   I was excited when I found such an old hymn that mentioned the dulcimer in its lyrics, but have since learned that it's unlikely that its use here refers to either of the two types of instruments, mountain or hammered, that we mostly associate with that word today.  The "dulcimer" of Biblical times was more likely a lute-like instrument.  Still, drawing a comparison of the "sweet sound" of the dulcimer, in any form, with a heavenly voice, is definitely appropriate.

His voice, as the sound of the dulcimer sweet, is heard through the shadows of death;
The cedars of Lebanon bow at His feet, the air is perfumed with His breath.
His lips as the fountain of righteousness flow, that waters the garden of grace,
>From which their salvation the Gentiles shall know, and bask in the smiles of His face.

O! Thou in Whose presence my soul takes delight, on Whom in affliction I call;
My Comfort by day, and my Song in the night, my Hope, my Salvation, my All—
Where dost Thou at noontide resort with Thy sheep, to feed on the pastures of love?
Say, why in the valley of death should I weep, or ’lone in the wilderness rove?

O! why should I wander an alien from thee, and cry in the desert for bread?
Thy foes will rejoice when my sorrows they see, and smile at the tears I have shed.
Ye daughters of Zion, declare, have you seen the Star that on Israel shone?
Say if in your tents my Belovèd hath been, and where, with His flock, is He gone?

“What is thy Belovèd, thou dignified fair? What excellent beauties hath He?
His charms and perfections be pleased to declare, that we may embrace Him with thee.”
This is my Belovèd, His form is divine; His vestments shed odor around;
The locks on His head are as grapes on the vine, when autumn with plenty is crowned.

The roses of Sharon, the lilies that grow in the vales, on the banks of the streams
On His cheeks in the beauty of excellence blow; His eyes are as quivers of beams.
His voice as the sound of the dulcimer sweet is heard through the shadows of death;
The cedars of Lebanon bow at His feet, the air is perfumed with His breath.