Gambling itself is not a sin. If it's done for fun and responsibility, with full acceptance that it is a game of chance. Some supposed Christians would claim the "gambling" we do here is sinful. They are idiots. And they certainly do not know the Bible.
The love of money, however
... If that is your purpose and devotion to gambling, you are definitely playing with fire and likely leading down a road of ruin.
Proverbs 13:11: Wealth gained hastily will dwindle, but whoever gathers little by little will increase it.
Hebrews 13:5: Keep your life free from love of money, and be content with what you have, for he has said, “I will never leave you nor forsake you.”
Matthew 6:24: “No one can serve two masters, for either he will hate the one and love the other, or he will be devoted to the one and despise the other. You cannot serve God and money.
Ecclesiastes 5:10: He who loves money will not be satisfied with money, nor he who loves wealth with his income; this also is vanity.
1 Timothy 6:9-10: But those who desire to be rich fall into temptation, into a snare, into many senseless and harmful desires that plunge people into ruin and destruction. For the love of money is a root of all kinds of evils. It is through this craving that some have wandered away from the faith and pierced themselves with many pangs.
Luke 12:15: And he said to them, “Take care, and be on your guard against all covetousness, for one's life does not consist in the abundance of his possessions.”
Ephesians 4:28: Let the thief no longer steal, but rather let him labor, doing honest work with his own hands, so that he may have something to share with anyone in need.
Proverbs 28:22: A stingy man hastens after wealth and does not know that poverty will come upon him.