We will go into his tabernacles - His tents, or the fixed resting place prepared for the ark. This is evidently language supposed to have been used on bringing up the ark into its place in Jerusalem: language such as they may be supposed to have sung or recited on that occasion.

We will worship at his footstool - See the notes at Psalm 99:5. The meaning is, the footstool of God: let us bow humbly at his feet. The language denotes profound adoration. It expresses the feelings of those who bare the ark to its assigned place.

Psalm 132:7 Parallel Commentaries

Manner of Covenanting.
Previous to an examination of the manner of engaging in the exercise of Covenanting, the consideration of God's procedure towards his people while performing the service seems to claim regard. Of the manner in which the great Supreme as God acts, as well as of Himself, our knowledge is limited. Yet though even of the effects on creatures of His doings we know little, we have reason to rejoice that, in His word He has informed us, and in His providence illustrated by that word, he has given us to …
John Cunningham—The Ordinance of Covenanting