Gambling is a sin. Why is it a sin? It is a sin because it violates principles of Godly living. As much as possible, we don't want to owe the world anything. See the wonderful example of Abraham in this regard: Genesis 14:22,23.
Playing the lottery or indulging in other forms of gambling is a witness to the world that we put our trust in Mammon - worldly wealth - and not in God's providence (Matthew 6:24). Some argue that perhaps God wants us to win the lottery, or the jackpot, or the horse race so we can do good with the money. Ok then, put that theory to the test. Buy one ticket - that's all it should take if the theory is true. If you don't win then never buy another lottery ticket because God has demonstrated to you that He is not going to use the world's wealth to bless you. Don't be fooled. If you continue to purchase tickets after that, you are just rationalizing your sinful greed and compounding the error by pretending to have a holy motive.
The Bible warns us against the love of money 1 Timothy 6:10; Hebrews 13:15; Proverbs 13:11; 23:5; Ecclesiastes 5:10. Wealth gained without work - "by vanity" or "for nothing" is wrong but wealth accumulated through honest labour is a blessing.
On a practical level, the fact that your chances of winning are so slim as to be next impossible means that you are throwing away on something useless the resources with which God has blessed you.
Look at it this way: where I live, in Ontario, Canada, there is a lottery called the 6/49. You have to correctly pick 6 numbers from 1 to 49 to win this lottery. That means you have 1 chance in 13,983,816 of winning this lottery. What does that mean? Here are some other odds for the sake of comparison:
- You have about a 1 in 2,000,000 chance of being struck by lightning.
- A pregnant woman has a 1 in 705,000 chance of giving birth to quadruplets.
- Someone eating an oyster has a 1 in 12,000 chance of finding a pearl in the oyster's shell.
You are more than 6X likely to be struck by lightning than to win the lottery and more than 10,000 times more likely to find a pearl in an oyster. So besides being sinful, it is just plain stupid to waste money on the lottery.
One Government official in charge of the lotteries in Egypt, in an interview with the CBC some years ago, described lotteries as "a kind of tax for fools." If you look at it that way you might think twice about buying a ticket. Look at a lottery ticket as a receipt for being stupid but not only that it is a record of a sinful desire to acquire the world's riches for nothing. If you love Mammon, you can't love God. When you step into the line to buy a lottery ticket, play a slot machine, bet on the horses you have made a choice between God and Mammon and it's the wrong choice!
I hope you have found this helpful.