There are many reasons for homelessness. Natural disaster, a loss of work, domestic violence, abandonment, crushing troubles, addictions, child abuse, sex trafficking or effects of past trauma. Few who are homeless choose to stay homeless and few realize that most people are one or two crises away from the same kind of desperate situation.
As for the homeless, those sick and in prison, those hungry and thirsty, those a stranger or naked that you help, Christ said, "Truly, I say to you, as you did it to one of the least of these my brothers, you did it to me." Matthew 25:40