Ananias and sapphira

This section of narrative in Acts 5:1-10 has troubled me for many years since being turned on to God's amazing grace. If the wealth of scriptures that describe that God will never be angry with us again, never hold our sins against us, will not remember ours sins etc are true then what about Ananias and Sapphira? Well after studying the book of Acts for well over 6 months now and after spending some prolonged time over this particular passage, God showed me something interesting that previously I had not seen. I'll show you this from the king James version. The story of this pair ends at v10 and then v11 describes the people's response, v12 gives a description of the power the church was experiencing then v13 says something a little odd!

'And OF THE REST DURST NO MAN JOIN HIMSELF TO THEM: but the people magnified them'

So does that mean the church was experiencing God's power but was not growing in number? The answer is 'No' It was growing because of the next verse v14

'And BELIEVERS were the more added to the Lord, multitudes both of men and women'

So what is v13 saying??

There were men and women who liked what they saw, wanted a piece of the action and joined themselves to the church but were not believers, they were merely spectators wanting a share in what was happening but not yet BELIEVERS. Of which were Ananias and Sapphira,

Notice also at 5:1 that Ananias is described as 'a certain man' rather than 'a disciple' or 'believer'

In v3 Peter asks an unusual question 'why has Satan filled your heart to lie to the Holy Ghost..?'
rather than 'why did you lie to the Holy Ghost?' its a question about his heart condition, the real issue was whether he was trusting in Jesus and not why he did what he did. A relevant response to such a question would be something like ' He has filled my heart because....' I suggest that satan had access to his heart because his heart was vacant rather than filled with the Holy Spirit.

Anyone have anything to add?