The Starfleet oath is an oath taken by Starfleet officers and enlisted personnel. It includes vows to "seek out life" and to defend the Federation and its principles.
Captain Kathryn Janeway was appalled at Captain Rudolph Ransom's murdering of innocent aliens to get his ship home, reminding him that he took an oath as a Starfleet officer which includes the meaning "to seek out life, not destroy it!" (VOY: "Equinox")
- Janeway's "To seek out life" can be a reference by the scriptwriters to the line "To seek out new life...", which was first used in the original Star Trek opening.
When the Cardassians accused Chief Miles O'Brien of secretly providing Starfleet weapons to the Maquis, O'Brien assured Odo that he had not violated his "oath to defend the Federation and what it stands for." (DS9: "Tribunal")
As Lieutenant Jadzia Dax was preparing to depart Deep Space 9 with three Klingons, in order to help them avenge their sons' murders and thereby fulfill the terms of a blood oath taken by Curzon Dax, Captain Benjamin Sisko reminded her that she had also taken an oath when she joined Starfleet. (DS9: "Blood Oath")