Serving the Lord with gladness, according to the dictionary, means to serve Him while showing joy, being brightly cheerful, and having an inner feeling of contentment and gratification. Because the Lord of the universe allows us to actually have a part in building His kingdom, we "raise a glad cry" (Is 44:23). We gratefully tell the Lord: "I will be glad and exult in You; I will sing praise to Your name, Most High" (Ps 9:3).
This gladness transcends our circumstances. From his prison, St. Paul tells his coworkers: "Even if my life is to be poured out as a libation over the sacrificial service of your faith, I am glad of it and rejoice with all of you. May you be glad on the same score, and rejoice with me!" (Phil 2:17-18)
When we serve the Lord with gladness, others catch on. In this Great Jubilee year, God especially wants all people to "be glad in the Lord and rejoice" (Ps 32:11; see also Ps 67:5). God promises: "The lowly will hear Me and be glad" (Ps 34:3). Many will tell the Lord: " 'You changed my mourning into dancing; You took off my sackcloth and clothed me with gladness' (Ps 30:12). 'You are my Shelter; from distress You will preserve me; with glad cries of freedom You will ring me round' (Ps 32:7). 'When cares abound within me, Your comfort gladdens my soul' (Ps 94:19). 'Therefore my heart is glad and my soul rejoices, my body, too, abides in confidence' " (Ps 16:9).
"Hear the sounds of joy and gladness" (Ps 51:10). "Meet with joy and gladness" (Is 35:10). "Serve the Lord with gladness."