A police summary of facts says the pair and a third person went to an address in Park Rd North, Hastings, tapping on windows to attract the attention of the occupants who kept quiet to pretend no one was home.
One of the visitors entered through a window and opened a door to allow his associates in before they burst into a living room as one occupant was calling the police.
Lewis then attacked one occupant with "a sword similar to that of a samurai sword", the first strike aimed at the head was deflected as the man fell to the ground with a gash and a broken arm.
Stewart had attacked and punched a female occupant.
Lewis used a steel chain as a weapon during the attack.
The male complainant managed to flee to get help, and the intruders turned their attention to the second occupant, Lewis hitting her in the head with the handle of the sword as he demanded: "Where's the money?"
She was also stomped and kicked by the pair before they left with the third person in a vehicle in which they had arrived at the address.
The male victim later required emergency surgery, with other injuries including a 10cm-deep cut through his bicep and a cut across the width of his back. His fellow complainant received bruises to the head and arms and also suffered burst blood vessels in one eye.
Lewis later told police he knew nothing about the attack and claimed he had been home all night with his flatmates.