What is the ruling on a false oath sworn by a person before a judge to deny threatening another with murder, and what is its expiation?

An-Nabi al-Ghamus (the perjured oath) is swearing a false oath. It is called so because it immerses its taker in sin or in Hellfire. Most scholars are of the opinion that there is no expiation for it except repentance and seeking forgiveness. The Shafi'is, however, believe that an expiation for the oath is obligatory in addition to that (feeding ten poor people, clothing them, or emancipating a slave; or fasting three days if one cannot afford the former). It is better and more cautious to offer expiation to avoid disagreement. It is not permissible to threaten someone with death merely for a verbal dispute. The correct approach is to complain to the ruler, and it is preferable to pardon and forgive. Swearing a false oath is not permissible except in cases of extreme necessity, such as obtaining a right or warding off harm.