Jacob's trouble

“How awful that day will be! None will be like it. It will be a time of trouble for Jacob, but he will be saved out of it.” Jeremiah 30:7
‘Jacob’s trouble’ is a term used of the Great Tribulation, also called ‘the day of the Lord’ in the Old Testament. Obviously it is not a single day, but a period of time. There’s no inconsistency here; we still use the word ‘day’ to refer to a period of time longer than a day (e.g. ‘someday’).
What’s interesting to note here is that the Great Tribulation is Jacob’s trouble. It is not the earth’s trouble, although the earth will also be in trouble. It is also not the church’s trouble (in fact, I believe the church will be removed prior to the Great Tribulation). The primary purpose of the Great Tribulation is for Israel to come to a point of acknowledging Jesus as their Messiah (see Zech. 12:10). But here, in Jeremiah, it is not called ‘Israel’s trouble’, but ‘Jacob’s trouble’. As we know, after the angel of the Lord wrestled with Jacob, He gave him a new name. From Jacob (‘heel-catcher’, or ‘deceiver’), he became Israel (‘a prince with God’). But in the Genesis narrative after this, Jacob is still called Jacob most of the time. A few times he is called Israel, but it is not a complete name change from that point on as it was for Abraham. As we look closer at the instances where ‘Israel’ and ‘Jacob’ are used, we see that ‘Jacob’ refers to him acting in his own flesh, while ‘Israel’ refers to when he is acting in tune with God. So too with the nation Israel. At the moment they are (generally speaking) living as any other nation in the world, with little thought of God. It is this nature that God will purge out of them in the Great Tribulation, so that they too may be ‘princes with God’.