Question: 'Should a Christian invest money in the stock market?'
Answer:

1. Is The Stock Market Gambling

Investing in stock. Some say this is gambling, but what is stock? Stock is a means for people to become part owners of a company. Buying stock is no more inherently gambling than is ownership of any other business. The intent is to make a profit by producing something of benefit to customers.

There are those who oppose investment in the stock market, saying that buying stocks is the equivalent of gambling. The argument goes that, since stocks are bought in the hope (not guarantee) that they will increase in value, it is a form of gambling. There are differences, however, between gambling at a casino or buying lottery tickets, and buying stock. Gamblers risk money, which they know they will probably lose, in the hopes of making money quickly. Wise investors buy partial ownership in a company in the hopes of making money over time, which can be a sound way to plan for the future.

Is The Stock Market Gambling

The difference really comes down to intent. Some types of investing, such as day-trading, are very much like gambling. Anything that requires 'luck' above wise decision-making and long-term planning should be avoided. Most long-term investments return a profit over time, making them much more like buying bonds or certificates of deposit than rolling dice in a casino. There are many who use investments to secure retirement, education for their children, and inheritance for their families.
The Bible offers quite a few examples of growing wealth through legitimate means. Some are similar to investing—spending money now to make money later. God’s intentions for how we should manage our wealth are found in many Scriptures. The following are a few examples.
Proverbs 28:20 says, “A faithful man will be richly blessed, but one eager to get rich will not go unpunished.” This speaks against the “get-rich-quick” mentality. Looking at investment as a long-term plan for the future is good planning, but trying to make a fortune overnight is not.
Second Corinthians 9:6 says, “Remember this: whoever sows sparingly will reap sparingly, and whoever sows generously will reap generously.” The context is actually speaking about investing in our relationship with God, but it demonstrates how one must often sacrifice now to gain in the future. Similarly, Proverbs 3:9-10 says, “Honor the Lord with your wealth, with the first fruits of all your crops; then your barns will be filled to overflowing, and your vats will brim over with new wine.”
Much of the Bible’s teaching about wealth is a warning against putting trust in wealth rather than in the Lord (e.g., 1 Timothy 6:17-18) or to the detriment of those who depend on us (e.g., Ecclesiastes 5:13-14). As long as we honor our commitments to God and our families with our money, and maintain a spirit of generosity and thankfulness, investing is an option Christians can consider.