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 Psalms 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.