Revelation 11:13

‘And in that hour there was a great earthquake and the tenth part of the city fell and seven thousand people were killed in the earthquake, and the remainder were terrified and gave glory to the God of Heaven.'

Now that God's people have been taken up the world faces the judgment of God. There will be delay no longer. The immediate effect of this is the great earthquake, in which God takes His tithe of one tenth of the city, the firstfruits for judgment. And seven thousand people die. This latter number parallels the number of the remnant in the time of Elijah (1 Kings 19:18). (Elijah lies behind many references in Revelation; compare Revelation 13:13 for the anti-Elijah). Thus this ‘seven thousand' is a reminder of the remnant whom they have been attacking. God's remnant have been put to death by the people of Jerusalem, now God claims a life for a life. The numbers are round numbers and not to be taken exactly, as with all large numbers in Revelation.

The remainder, in fear, ‘give glory to the God of Heaven'. It is doubtful if this is the language of conversion. Rather in what they face they have to acknowledge God's remote greatness but their hearts are still far from Him. It is not a response of faith. Compare how in Revelation 16:10 men blaspheme the God of Heaven. The title is used of man's instinctive reaction to God as the unknown. Jerusalem is a religious city, which explains the differing response to what occurs, but that does not necessarily go far enough. Submission to Christ is required and they have rejected the testimony of the witnesses.