Wanting to analyze your question directly actually you could have made him interested in the business by giving him the money. Suppose you gave him money and he placed a bet on gambling and won but that is not the end because it made him greedy for gambling. Later he would save money and place a gambling bet and lose. Gambling is proven to be a game of luck so it doesn't always win. If you want lend him the money and ask him to repay it in daily wages. We don't all have the same financial position so we shouldn't call anyone to gamble.