The phrase "set asunder" means to separate, divide, or break apart. Some antonyms for this phrase could include unite, connect, join, or reconcile. When people come together and work towards a common goal or harmonious relationship, they are uniting and might be able to avoid being set asunder. Connecting can mean physically linking two things together, but can also mean creating a mental or emotional bond. When people join forces, they pool their resources and efforts, making them stronger together. Finally, reconciliation means the restoration of a friendly or peaceful relationship, which might have been threatened by being set asunder.