To stand by

to aid, to support.
To be near; to be a spectator; to be present
To be aside; to be set aside with disregard
To maintain; to defend; to support; not to desert; as, to stand by one's principles or party.
- Dr. H. More.
To rest on for support; to be supported by
To remain as a spectator, and take no part in an action; as, we can't just stand idly by while people are being killed.
- Whitgift.

See also: By, Stand, Stand, Stand, Stand, Stand