Jargon!

A lot of the time, we don't understand what we're singing during praise. Obviously we probably get most of it, but we tend to throw away catch phrases like Hosanna and Hallelujah without much thought to what they actually mean. What does it mean to sin Hallelujah? John Piper helpfully explains (you can read the whole thing here):

The English word “hallelujah” is a transliteration of two Hebrew words, hallelu and jah. The first word, hallelu, is the second person imperative of “praise.” The second word, “jah,” is the short form of Jahweh (or Yahweh).

So when we say, “Hallelujah!” we are exhorting others (people and angels) to join us in praising Yahweh.

What gives a punch to my singing, “Hallelujah,” is that Jah (=Yahweh) is not a generic word for God, but the personal name of the God of Israel.

To shout, “Hallelu Jah!” — “Praise Jah!” — is like standing in the council of the gods and boldly saying, “Not to you, Molech!” “Not to you, Baal!” “Not to you, Dagon!” “Not to you, Artemis!” “Not to you, Zeus!” But to Jah, and Jah alone, I give praise. And I call you to join me! Praise Jah!

And not only is Jah God’s personal name, but it is the one he gave himself to distinguish himself from all the gods. And it is thrilling in meaning.

Hallelujah!