"Worship the LORD in holy attire; Tremble before Him, all the earth."
The Christian is clothed in the holiness of Christ; His grace and mercy, forgiveness and justification are our "holy attire". It is the pure white linen of Christ that covers our guilt and shame and makes us acceptable to worship the Lord. And we worship in reverence and awe; careful not to trivialize Him. "There is a sacred trembling which is quite consistent with joy, the heart may even quiver with an awful excess of delight. The sight of the King in His beauty caused no alarm to John in Patmos, and yet it made him fall at his feet as dead. Oh, to behold Him and worship Him with prostrate awe and sacred fear!" (Spurgeon)