Jesus wants intimates, not inmates.
Martha, scrambling around, sweating over "Sunday dinner", setting the table, seeing to the guests...
...and Mary, seeing to Jesus.
Martha had allowed her focus to become diffused and diluted until Jesus was nothing more than another party guest in the periphery (how often do we allow this in our lives, or worse yet, in our churches?), while Mary was mesmerized by her Master, thoroughly enraptured, seeming to sense the sacred intimation of the moment, hanging on every word...
...For her, there was nothing but Jesus.
Jesus met Martha's aggravation at her sister's seemingly sedentary behaviour with affirmation of Mary's choice and an implied invitation for Martha to opt for the same singlemindedness her sibling had found.
Fast forward to another feast, also at the home of the two sisters, six days before the Passover, six days before Jesus' execution:
Martha is still serving, and again, Mary's uncanny sense of the sacred steals the show. She knows somehow that time is short; devotion displaces decorum and protocol is pushed aside by passionate love for her Lord. She produces a pound of pure nard, worth a year's wages, and pours out this, her most precious possesion, to Jesus.
Once again, Jesus chastises those present for chiding Mary, not wanting this moment between them diminished in any way by the pettiness of paltry objections.
In both scenarios, Martha offered service to Jesus, Mary offered herself.
Jesus didn't love Martha any less, He just wanted her to know the freedom Mary knew of loving Him more.
"One thing is needed"
-Luke 10:42
-Luke 10:38-42
-John 12:1-8