1 Strength is compared here to a belt that one wears for support. The Lord’s power undergirds his rule.
2 Heb “from antiquity [are] you.” As the context suggests, this refers specifically to God’s royal position, not his personal existence.

In other versions

The Lord reigns; he is robed in majesty;

the Lord is robed; he has put on strength as his belt.

Yes, the world is established; it shall never be moved.

Your throne is established from of old;

you are from everlasting.

The Lord reigns, he is robed in majesty;

the Lord is robed in majesty and armed with strength;

indeed, the world is established, firm and secure.

Your throne was established long ago;

you are from all eternity.

The Lord reigns! He is robed in majesty;

the Lord is robed, enveloped in strength.

The world is firmly established;

it cannot be shaken.

Your throne has been established

from the beginning;

you are from eternity.

The Lord is king! He is robed in majesty.

Indeed, the Lord is robed in majesty and armed with strength.

The world stands firm

and cannot be shaken.

Your throne, O Lord, has stood from time immemorial.

You yourself are from the everlasting past.

Yahweh is king; he clothes himself with majesty.

Yahweh clothes himself; he girds himself with might.

Yes, the world is established so that it will not be moved.

Your throne is established from of old;

you are from everlasting.

The Lord reigneth, he is clothed with majesty;

The Lord is clothed with strength, wherewith he hath girded himself:

The world also is stablished, that it cannot be moved.

Thy throne is established of old:

Thou art from everlasting.

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