If the speakers are passive then you would need an amplifier with the correct input to connect the audio output of your TV. This could be an AV receiver. If the TV input is digital and the amp doesn't have digital inputs you can get a digital to analog converter to connect the TV to the amp.
If the speakers are self powered (active) you might need the same converter to connect them directly to the TV if the TV doesn't have analog audio our or a headphone jack.