'Gladness' in the Bible

Moreover Hezekiah the king and the princes commanded the Levites to sing praise unto the LORD with the words of David, and of Asaph the seer. And they sang praises with gladness, and they bowed their heads and worshipped.

And the children of Israel that were present at Jerusalem kept the feast of unleavened bread seven days with great gladness: and the Levites and the priests praised the LORD day by day, singing with loud instruments unto the LORD.

And the whole assembly took counsel to keep other seven days: and they kept other seven days with gladness.