Pseudo-Chrysostom
Catena Aurea · Matthäusevangelium 6
And when thou prayest, thou shalt not be as the hypocrites are; for they love to pray standing in the synagogues and in the corners of the streets, that they may be seen of men. Verily I say unto you, They have their reward. But thou, when thou prayest, enter into thy closet, and when thou hast shut thy door, pray to thy Father which is in secret; and thy Father which seeth in secret shall reward thee openly.
Prayer is as it were a spiritual tribute which the soul offers of its own bowels. Wherefore the more glorious it is, the more watchfully ought we to guard that it is not made vile by being done to be seen of men.