I think it is quite likely that the Christian attitude to wealth softened as a result of the promised new order not being quite as imminent as supposed!
What do you mean? The kingdom came in AD 70. It was imminent and near, as Jesus said it was.
In Luke 6 verses 20-23 praise poverty and 24-26 condemns riches.
20 Looking at his disciples, he said:
“Blessed are you who are poor,
for yours is the kingdom of God.
21 Blessed are you who hunger now,
for you will be satisfied.
Blessed are you who weep now,
for you will laugh.
22 Blessed are you when people hate you,
when they exclude you and insult you
and reject your name as evil,
because of the Son of Man.
23 “Rejoice in that day and leap for joy, because great is your reward in heaven. For that is how their ancestors treated the prophets.
24 “But woe to you who are rich,
for you have already received your comfort.
25 Woe to you who are well fed now,
for you will go hungry.
Woe to you who laugh now,
for you will mourn and weep.
26 Woe to you when everyone speaks well of you,
for that is how their ancestors treated the false prophets.
I think Christianity may have started out very ascetic and un-materialist but softened somewhat fairly quickly.
Matthew 16:27-28 (NASB)
27 For the Son of Man is going to come in the glory of His Father with His angels, and will then repay every man according to his deeds.
28 “Truly I say to you, there are some of those who are standing here who will not taste death until they see the Son of Man coming in His kingdom.”
How was the Son of Man - Jesus - going to come (The Second Coming)? It was in the same manner the Father came to a nation in the OT. "In the glory of God." God's presence was recognized by the armies that God sent to judge a nation according to their deeds. Now, during the 1st-century, Jesus is telling His disciples that some standing in His midst will not die before He comes again (The Second Coming).
Daniel, in Daniel 2:44-45 said,
Daniel 2:44-45 (NASB)
The Divine Kingdom
44 In the days of those kings the God of heaven will set up a kingdom which will never be destroyed, and that kingdom will not be left for another people; it will crush and put an end to all these kingdoms, but it will itself endure forever. 45 Inasmuch as you saw that a stone was cut out of the mountain without hands and that it crushed the iron, the bronze, the clay, the silver and the gold, the great God has made known to the king what will take place in the future; so the dream is true and its interpretation is trustworthy.”
So, during the time of those kings/Caesars God would set up the eternal kingdom. The fourth kingdom in the king's dream was the Roman Empire. So the kingdom was set up at that time. It happened in AD 70.
Jesus and the disciples repeatedly said that His kingdom and His time of coming was near, at hand.
so, you too, when you see all these things, recognize that He is near, right at the door.
Even so, you too, when you see these things happening, recognize that He is near, right at the door.
and heal those in it who are sick, and say to them, ‘The kingdom of God has come near to you.’
So you also, when you see these things happening, recognize that the kingdom of God is near.
“Repent, for the kingdom of heaven is at hand.”
From that time Jesus began to preach and say, “Repent, for the kingdom of heaven is at hand.”
And as you go, preach, saying, ‘The kingdom of heaven is at hand.’
What is more, Jesus taught the kingdom of God is a spiritual kingdom, even in their midst since where the King is the kingdom is also there.
Luke 17:20-22 (NASB)
20 Now having been questioned by the Pharisees as to when the kingdom of God was coming, He answered them and said, “The kingdom of God is not coming with signs to be observed; 21 nor will they say, ‘Look, here it is!’ or, ‘There it is!’ For behold, the kingdom of God is in your midst.”
So, the kingdom came in AD 70.