Do you not know that to whom you present yourselves slaves to obey, you are that one’s slaves whom you obey, whether of sin leading to death, or of obedience leading to righteousness? But God be thanked that though you were slaves of sin, yet you obeyed from the heart that form of doctrine to which you were delivered.  Romans 6:16,17.

Obeyed, hupakouo, Strong’s # 5219: To hear as a subordinate, listen attentively, obey as a subject, answer and respond, submit without reservation. This is a word picture of servants who are attentive to requests made of them and who are of a willing heart. The word contains the idea of hearing, responding, and obeying.