If there were some solitary or feral man, the passions of the soul would be sufficient for him; by them he would be conformed to things in order that he might have knowledge of them. But because man is naturally political and social, there is need for one man to make his conceptions known to others, which is done with speech. So significant speech was needed if men were to live together. Which is why those of different tongues do not easily live together.
Thomas AquinasDo not wish to jump immediately from the streams to the sea, because one has to go through easier things to the more difficult.
Thomas AquinasTo restore man, who had been laid low by sin, to the heights of divine glory, the Word of the eternal Father, though containing all things within His immensity, willed to become small. This He did not by putting aside His greatness but by taking to Himself our littleness.
Thomas Aquinas