Arenas, who lives in Southern California, says he regularly plays the Mega Millions lottery game.
But recently, while going to get his numbers at his usual gas station in Calabasas, he was low on gas and forgot all of his cash except for $10.
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So he went to a different station, where he encountered a homeless man asking for change.
Arenas said he needed the money for gas but offered the man $5.
The man said no to the money, and Arenas said when he won the lottery the homeless man would get a cut.
Arenas ended up winning $300,000 and gave the man his share.
Arenas said the homeless man hugged him for five minutes, cried and then began to pray.