God desires to see all his children pray with one voice.
In an age of division, one thing that pleases God the most is to see his children pray with a united voice.
This is something best described by St. Cyprian in a treatise on the Lord’s Prayer.
The God of peace and the Master of concord, who taught unity, willed that one should pray for all, just as he himself, being one, carried us all. The three children observed this law when they were shut into the fiery furnace, praying with one voice and with one heart: thus our faith in divine Scripture teaches us, and, as it teaches us how such people prayed, gives us an example that we should follow in our own prayers, so that we may become like them: Then these three sang a hymn as if with one mouth, and blessed the Lord. They spoke as if with one mouth, even though Christ had not yet taught them how to pray.
Not only did God desire us to pray with one voice, he has shown that this is one of the most fruitful types of prayer.
And therefore, as they prayed, their prayers were heard and were fruitful, because a peaceful, sincere, and spiritual prayer deserved well from the Lord. Thus, too, we find the Apostles and the disciples praying after the ascension of the Lord: They all continued with one accord in prayer, with the women and with Mary who was the mother of Jesus, and his brothers. They continued with one accord in prayer, showing, by the urgency and the unanimity of their praying, that God, who makes the inhabitants of a house to be of one mind, only admits to his divine and eternal home those among whom prayer is unanimous.
It is an important lesson, showing us that God greatly desires us to be unified in prayer, all praying together in one family.