'Theirs' in the Bible

Blessed are the poor in spirit: for theirs is the kingdom of heaven.

Blessed are they that have been persecuted for righteousness'sake: for theirs is the kingdom of heaven.

But beware of men: for they will deliver you up to councils, and in theirs synagogues they will scourge you;

But they shall proceed no further. For their folly shall be evident unto all men, as theirs also came to be.

For men swear by the greater: and in every dispute of theirs the oath is final for confirmation.