John Gill Commentary Psalms 63:2

"So have I looked upon thee in the sanctuary, To see thy power and thy glory." — Psalms 63:2 (ASV)

To see thy power and thy glory
Either the ark, as the Jewish writers generally interpret it; the symbol of God's presence and glory, and which is called his strength and his glory; see (Psalms 78:61) (132:8) ; or rather the Lord Christ, who is the power of God, as well as the wisdom of God; by whom he made the world, and upholds it; by whom he has redeemed his people, and keeps and preserves them; and whose power is seen in the efficacy of the word and ordinances: and who is also the glory of God; he is the brightness of his Father's glory; his glory is the glory as of the only begotten of the Father; he has the same glorious nature, perfections, names, homage, and worship; and the glory of all the divine attributes is displayed in the work of salvation and redemption he has wrought out; and this glory is to be seen, through the glass of the word and ordinances, in the house of God. Hence it follows;

so [as] I have seen thee in the sanctuary ;
where he comes and blesses his people, and manifests himself unto them, as he does not unto the world; where his goings are seen, and his footsteps traced, (Psalms 68:24) . The psalmist calls to mind former experiences in the sanctuary; and these stimulate him to an eager desire of fresh tastes of the grace of God, and clearer views of his power and glory. Or, as in a dry and thirsty land my soul longed and thirsted for time, so have I desired to see thee in the sanctuary; or so I see thee there as if in the sanctuary.