Contradiction with Ecclesiastes 7:2
While Isaiah 30:29 speaks of joy and gladness, Ecclesiastes 7:2 emphasizes the wisdom in sorrow and the house of mourning.
Ecclesiastes 7:2: [It is] better to go to the house of mourning, than to go to the house of feasting: for that [is] the end of all men; and the living will lay [it] to his heart.
Contradiction with James 4:9
Isaiah 30:29 describes joy and celebration, whereas James 4:9 encourages believers to grieve, mourn, and wail, emphasizing seriousness over joy.
James 4:9: Be afflicted, and mourn, and weep: let your laughter be turned to mourning, and [your] joy to heaviness.
Contradiction with Proverbs 14:13
Isaiah 30:29 focuses on singing and gladness, but Proverbs 14:13 warns that laughter and joy can result in sorrow and heaviness.
Proverbs 14:13: Even in laughter the heart is sorrowful; and the end of that mirth [is] heaviness.
Contradiction with Ecclesiastes 3:4
While Isaiah speaks of perpetual joy, Ecclesiastes reminds us there is a time to weep and a time to mourn, indicating life's cyclical nature.
Ecclesiastes 3:4: A time to weep, and a time to laugh; a time to mourn, and a time to dance;