NOTES for Isa 12:1-2
For the prophet Isaiah "that day" is the day of the Lord, when God will manifest His presence and His power. The day, in which man turns out to be face to face with God, unless he hides from Him. But indeed, such a day has already come for us! God has fulfilled salvation through the Son, Who is with us every day, He sent the Comforter, Spirit filling our hearts of fearlessness, strength and song of praise. So, for us every day is the day of the Lord, and today also. Don’t we try to hide?