We don’t usually think about what we might have to say on any given day but it is useful to meditate on the 6 verses of Isaiah 12 when the prophet told Israel and tells us what “you will say on that day”.
How wonderful to be among those who will say, “Behold, God is my salvation; I will trust, and will not be afraid; for the LORD God is my strength …” (verse 2). Of course, believing in God and His Son should always be the foundation on which our strength rests – it is not physical strength is it! What strength of mind do you have? How much do you meditate on the ultimate future?
In verse 3 we read, “With joy you will draw water from the wells of salvation”. This takes our thoughts to what Jesus said to the Samaritan woman at the well, “… whoever drinks of the water that I will give him … (it) … will become in him (or her) a spring of water welling up to eternal life” (John 4:14). We link this saying with his words “on the last day of the feast” that the one “who believes in me … out of his heart will flow rivers of living water” (7:38). After Jesus left them, “the Spirit” (verse 39) was to flow out of the heart of the disciples to produce more of the words of God – on which we can (and must) feed.
Back to Isaiah, the last 2 verses vividly picture the time when the redeemed will “Sing praises to the LORD, for he has done gloriously … Shout and sing for joy. O inhabitant of Zion. For great in your midst is the Holy One of Israel”. These words take us to “the song of the Lamb” in Revelation 15. Let us live so that, by the grace of God, we will be there to experience and sing this “in that day”.
“Great and amazing are your deeds O Lord God the Almighty! Just and true are your ways, O King of the nations! … For you alone are holy. All nations will come and worship you, for your righteous acts have been revealed” (verses 3,4). At the moment they have been concealed, except to those who read and mediate on God’s word and prepare themselves for what they “will say (and sing) in that day”.