Cutting into gas line. Consequences.

[Lawson Cox]

I'm embarrassed for publicly asking this question but memory is unclear nowadays. If I cut into fuel line to swap out fittings at electric fuel pump which is mounted inside the frame rail close to the tank, the only gas that will drain out is the gas in the line, correct? No siphoning action of gas out of the tank, Correct? I can't believe I'm asking this question.