In both I Chronicles 16:10 and Psalm 105:3 it says ~ “Glory in His holy name; let the hearts of those rejoice who seek the LORD!”
The word “glory” in the Strong’s Concordance means “to praise, give thanks, cheer, extol; to be praised, be worthy of praise, be of renown, to make one’s boast in the name of God…”.
To ‘glory’ in His holy name would be to have one’s heart and mind set on fully worshiping the Lord, with pure and total abandonment. With one’s focus only on the Lord, without any awareness of one’s surroundings. Worshiping with a pure and loving heart, with awestruck excitement and joy.