Our pastor preached a sermon last sunday and we're still pondering over it. There's been some mixed up ideas but here's my thinking on it. It's about hebrews 12.

"My son, do not make light of the Lord's discipline,

and do not lose heart when he rebukes you,

because the Lord disciplines those he loves,

and he punishes everyone he accepts as a son."

The words I underlined discipline in both these cases probably refers to punishment or rebuke. (you can look at the dictionary.com results for the word discipline here) The bible seems to use  the same kind of example twicein the same verse, just in different words, to get the point across. It's mostly in psalms and proverbs. e.g:

Though you grind a fool in a mortar, grinding him like grain with a pestle, you will not remove his folly from him.

They used the same thing twice in different word, though it still had the same concept, to get the point across better than if they just said it once. That's what I think happened with the first two words: Discipline and rebuke. But I think the two others: discipline and punish, mean two different things. I think when they said punish, they meant punish. So... God punished for something we did wrong. No discipline ( or punishment) seems pleasant at the time, but painful. But he used that punishment as discipline, to bring us closer to him, through the trouble that were being punished with.