draw the line vs draw a line

draw the line and draw a line both are verbs.

Word	Noun	Adjective	Verb	Adverb
draw the line	No	No	Yes	No
draw a line	No	No	Yes	No

As verbs, draw the line and draw a line are synonyms defined as:

draw the line and draw a line: reasonably object (to) or set a limit (on)

draw the line (verb)	draw a line (verb)
reasonably object (to) or set a limit (on)	reasonably object (to) or set a limit (on)