Like the previous composition, Psalm 121 is a “song of ascents.” This may mean that worshipers would sing this particular psalm along with others as they headed to the elevated site of Jerusalem for worship at the temple.

The city is situated on a number of eminences. Since the temple was located on one of these, the “mountains” doubtless are those of the city. When praying, the psalmist apparently would look to the heights of Jerusalem, the representative location of YHWH’s dwelling. (Compare 1 Kings 8:30, 44, 45; Daniel 6:10[11].)

When answering his own question regarding the source of his help, the psalmist confidently responded that it was YHWH, the Creator of heaven and earth. The words “heaven and earth” are descriptive of the psalmist’s world consisting of the land bounded by the sea and the dome-like sky above.

Because God made “heaven and earth,” his ability to provide needed aid has no limits. He will uphold his servants, not allowing their feet to slip and experience a calamitous fall from which recovery would be impossible. Never is there a time when his aid cannot reach them. Unlike humans, he does not get sleepy, doze or sleep. His protective guardianship of “Israel” (his people collectively) and his faithful servants as individuals (“you” being singular) can always be relied upon.

For his individual servant, YHWH is the Guardian, providing protective shade from whatever may have the potential for causing injury. The Most High, like a faithful friend, would be there at the right side. Evidently representing protection generally, the psalmist alludes to being shielded during the day from the intense heat of the sun and at night, when the moon is shining, from the penetrating cold.

He had complete confidence that YHWH would protect his servant’s life (soul) from evil or trouble of every kind. YHWH’s protective care would be with his devoted servant upon leaving or returning home, both then and into the indefinite future.

Notes:

Regarding YHWH, see Psalm 1.

In verse 5, the largest of the Dead Sea Psalms scrolls indicates that YHWH’s guarding would be “by night.” Then, in verse 8, this scroll reads “he” (not YHWH).