John Calvin Commentary Genesis 19:6

"And Lot went out unto them to the door, and shut the door after him." — Genesis 19:6 (ASV)

And Lot went out at the door unto them. The fact that Lot went out and exposed himself to danger shows how faithfully he observed the sacred right of hospitality. It was truly a rare virtue that he preferred the safety and honor of the guests whom he had undertaken to protect to his own life; yet this degree of magnanimity is required from the children of God: that where duty and fidelity are concerned, they should not spare themselves.

And although he was already severely wronged by the siege of his house, he still endeavored, with gentle words, to soothe their ferocious minds, while he humbly pleaded with them to lay aside their wickedness and addressed them as brothers. This reveals how savage their cruelty was, and how violent the rage of their lust, since they were not at all moved by such extraordinary mildness.

But the description of such brutal rage serves to teach us that punishment was not inflicted on them until they had proceeded to the last stage of wickedness. And let us remember that the reprobate, when they have been blinded by the just judgment of God, rush, as if with minds wholly given over, through every kind of crime, and leave nothing undone, until they render themselves utterly hateful and detestable to God and humankind.