Stocks are a legitimate investment. Buying stocks is essentially no different than buying diamonds, land, or wheat. True, the stock market has an element of risk, but don't confuse 'lost wages' with 'Las Vegas.' Do you know of any business which involves no element of risk? If so, do you know their phone number?
Gambling, on the other hand, is a game where each person hopes to guess the right number on the dice, or pick the right horse. Gamblers are invalid as witnesses in a Jewish court.
The Sages of the Talmud differ as to why gamblers are invalid. According to one opinion, someone who wins a bet is like a thief, because he collects prize money that he didn't `earn' and to which he has no true legal claim.
According to another opinion, only a professional gamester – who has no other source of income – is invalid as a witness. His integrity is suspect, because he spends his day in pursuits which contribute nothing to society. According to this opinion, someone who gambles only part-time can be a valid witness, provided he's involved in some productive activity.
The following story is told about the Chafetz Chaim: A man once asked the Chafetz Chaim to bless him that he should win the lottery, but the Chafetz Chaim refused. "But you give blessings to people who gamble on stocks, why not when they gamble on lotteries?" the man asked. The Chafetz Chaim answered that he gives blessings to stock investors because if the stock goes up, no oneloses money. But blessing one lottery ticket is a 'curse' upon the other lottery tickets.
