The Cross of Malta, also called St. John, eight-pointed or octagon, is a symbol used since the 12th century as a insignia or venerated by the knights and nuns of the Order of St. John of Jerusalem (also called from Malta since King Charles I of Spain feuded with this island in the 16th century).
It is white because of the importance given to the purity to be had, both inside the heart and on the outside, without macula or stain. The eight tips of the cross are in memory of the eight beatitudes we must always have with us, the first will be spiritual satisfaction; the second, to live simply and without malice; the third, to live in humility; the fourth, weeping the faults and sins; the fifth, to love justice; the sixth, to be merciful; the seventh, to be clean and sincere of heart and thought; and eighth, endure afflictions and persecutions for justice. And these virtues must be engraved and kept in hearts, for the preservation of souls.