|On "New Testament Family Values"|
In Luke 2:41-49, we read a story that certainly doesn't present Joseph and Mary as exemplary parents. When Jesus was 12, the family traveled from Nazareth to Jerusalem to keep the feast of the Passover, and when it was over, his parents were returning home and had gone "a day's journey" before they noticed that Jesus was not in the company they were traveling in. It's hard to imagine how responsible parents could travel for an entire day and not know that their minor child had been left behind in the city they had visited. Ordinarily, a couple doing this would be considered parentally negligent, but if the couple should be the ones whom God chose as the parents of his son, that apparently made it all right, because the inspired writer said nothing critical about the favored couple.
Knowing how Jesus could be missed doesn't require imagination, it requires knowledge of the social context. In this period travelers often went around in large family or otherwise related groups for protection against robbers, and it was quite easy to lose track of a person; Pilch and Malina note that in leaving Jesus to the trust of kinfolk and acquaintances, Joseph and Mary were not being negligent at all, but were being normal ancient Mediterranean parents with an extended kinship group. On the other hand, at 12, Jesus was considered "of age" in Jewish society anyway.
If parents today should practice the family values that Jesus taught, they would save no money for tomorrow (Matt. 6:19-20) and apparently show no interest in providing for the needs of their families. They would not worry about what they would eat or drink or wear (Matt. 7:25-31), and in so doing would lead their families into poverty and even total destitution.
The ancients did not share our perception of money as a cure-all, and as Pilch and Malina note in the Handbook of Biblical Social Values, the ancients believed that all goods were limited and supply and had already been distributed (which, until the industrial age, they practically were). If Jesus is giving an incorrect emphasis here, then so was Seneca and Diogenes Laertes (who "praised the moral blessing of poverty"), Lucretius and Cato (who "condemned the danger of wealth"), and Dio Chrysostom (who along with Laertes said that wealth was worthless compared to knowledge). The ancients valued discipline and knowledge more than they did money.
Moreover, let it be kept in mind that there were neither banks nor credit unions available. Saving money meant using a strongbox which was either in the home or buried under the floor, where the danger of thieves and corruption was very real.
Note also the reference to moths: Jesus speaks here not of money per se, but of "treasures" -- possession like precious apparel, and precious metals that would rust away. In light of the passing nature of wealth in this context, sages advised people to be generous with their holdings and use them before the decayed. Ben Sira "admonishes his hearer to use money for a friend in need rather than letting it rust, for one would thereby lay up treasures in heaven." [Keener, Matthew commentary, 230ff]
In this age of electronic funds transfer and easy access to mutual funds and the stock market -- options never available, except to the very, very few and very, very rich after a fashion in the first century -- Jesus' advice would certainly not be the same. Capitalist economics opens opportunities never known under ancient Rome.
The reply to Matt. 6:25-31 (not Matt. 7) is made on similar grounds. Furthermore, almost all of Jesus' hearers were already in poverty and destitution, and weren't likely to be changing that anytime soon. See here for more.