Isaiah 12:4
And in that day shall ye say, Praise the LORD, call upon his name, declare his doings among the people, make mention that his name is exalted. And in that day shall ye say, Praise the LORD, call upon his name, declare his doings among the people, make mention that his name is exalted.
In that day God's gathered, redeemed people respond by praising the Lord, calling upon His name, declaring His doings among the people, and making mention that His name is exalted. That praise and witness are public and worldwide, to be made known among the peoples and nations and throughout the earth, so that His excellent deeds and excellent things are known in all lands. The verse belongs with the surrounding song spoken when anger is turned away and comfort is given, when God is trusted as salvation without fear, when the Lord Jehovah is strength and song and salvation, when water is drawn with joy from the wells of salvation, and when the inhabitants of Zion sing and cry out and shout because great is the Holy One of Israel in their midst. The name is exalted because God is the people's salvation, strength, and song, and because the Holy One of Israel is present among them.
That day is the day when the Lord shall set His hand again the second time to recover the remnant left from Assyria and Egypt and Pathros and Cush and Elam and Shinar and Hamath and the islands of the sea, when the root of Jesse shall stand for an ensign to which the Gentiles seek with glorious rest, and when an ensign is set up for the nations to assemble the outcasts of Israel and gather together the dispersed of Judah from the four corners of the earth. The song will be fulfilled in God's people when they lay aside burdens and enterprises not placed on them, obtain the robe of Christ's righteousness, answer Christ's prayer, and serve with all humility. The verse is the voice of the ransomed walking the royal highway cast up for travel to heaven as a better and safer way, and practicing it means seeing the Saviour as refuge and as a shield at the right hand defending from the arrows of Satan. The verse is a comforting word for that day, received when the Lord draws near in prayer with peace and joy in divine love.
The verse is a living assurance to be personally realized, bringing renewed courage and blessing and giving strength even in bodily weakness to speak words that help and bless others, including the sick. Seeing divine salvation and goodness leads to open praise and testimony, and trusting God rather than relying on human understanding makes goodness and power known in worship and witness. Such praise replaces mourning and complaining.