It is well-known that the Torah is called “Sweet Song” and this is also one of the ten methods of praying. The allusion is that one who is reading the Torah should read it with sweetness and happiness with the voice of a “sweet song”, and similarly prayer should be said with sweetness and happiness with the voice of a “sweet song”. This applies especially to “The song of the sea” and “Hallel” where the whole point of saying them is to be said with sweet singing and the sound of thanks. This is unlike the custom in certain places where “the runners went out urgently” with their reading like the reading of the hanging of the ten sons of Haman and this causes much anger and embarrassment on high when Hallel and the song of the sea are read like this.
In the same way saying the prayers, requests, entreaties and blessings hurriedly is a great denigration even if it between a man and his friend and far more when it is before a King of flesh and blood who would definitely become angry at such a voice and punish him with death as this is not requesting things and even to give commands to a servant in such a way is not right. All the more so before the King of all Kings, the Holy One Blessed be He.
In the same way one who reads the Torah hurriedly lowers their value and who knows how many mistakes he will make and in each reading of the Torah there are notes to sing the reading and their secrets are lofty and elevated and one who misses then out has destroyed much goodness. There is no value which can be ascribed to the recital of the Mishnah with tunes and the book of Tehillim which contains the songs of King David must definitely be read with a voice of thanksgiving and sweet song.