Fidelity is the practical expression of love. Fidelity is a love that is supported by loyalty and courage. It is keeping your promises to God, family and country.
Grant, O God, that my heart which was made for you alone, may ever be wholly yours; that free from all undue affection to creatures, it may refer all to you and seek you alone in all things. Yes, my God, I know, that you are the center of all hearts, because you are their last end and sovereign good and that they cannot rest until they rest in you. Grant me, therefore, what I ask now: a faithful, sovereign, and constant adherence to you. Amen
Fidelity is the quality of being faithful or loyal. Its original meaning regarded duty to a lord or a king, in a broader sense than the related concept of fealty. Both derive from the Latin word fidēlis (A III adjective), meaning “faithful or loyal”.