What is the ruling on using the term "brother" for a non-Muslim with the intention of human or national fraternity, not religious, and what is the ruling on congratulating Christians on their holidays if the interest necessitates it, based on the principle of choosing the lesser of two harms or the better of two benefits?

Using the word "brother" for a disbeliever is impermissible if it implies religious brotherhood. However, if it signifies brotherhood by lineage, then there is no harm in it, as Al-Qurtubi stated in his interpretation of the Almighty's saying: (And to 'Ad [We sent] their brother Hud) and (When their brother Noah said to them), that it refers to brotherhood by lineage or kinship.

However, one must be cautious about frequently using this word unnecessarily, for fear of inclining one's heart and showing affection towards disbelievers, as loving them is forbidden and diminishes one's faith, according to the Almighty's saying: (You will not find a people who believe in Allah and the Last Day loving those who oppose Allah and His Messenger).

It is not permissible to congratulate Christians and other polytheists on their holidays, which are specific to their religion. Congratulating them on holidays like Easter is a contradiction of the explicit Quran, which states that Jesus, peace be upon him, was not crucified.