Be the master of your senses. The soul is portrayed as the driver of the carriage (human body) and the horses are the senses which should be kept under our control.
"One who is able to withdraw his senses from sense objects, as the tortoise draws its limbs within the shell, is firmly fixed in perfect consciousness." - Chapter 2 Verse 58
"The senses are so turbulent that they can forcibly lead astray the mind of even a vigilant person of sound judgement" -Chapter 2 Verse 60
"One whose senses have been brought under control is established in perfect knowledge" - Chapter 2 Verse 61
"One who can control his senses by practicing the regulated principles of freedom can obtain the complete mercy of the Lord and thus become free from all attachment and aversion." Chapter 2 Verse 64