The first centuries in the church had the practice of receiving Holy Communion in some way in the hand, but I will now explain that it was an essentially different gesture than now. The body of Christ was placed on the right palm of the hand, not on the left as now, but on the right hand, and the communicant had to bow deeply with his head down to the palm of the hand and receive immediately with the mouth the sacrament, without touching it with the fingers. It was not permitted to touch it with the fingers.
It was at the same time a gesture of adoration. You had to bow down deeply with your head and take the Holy Sacrament, and then you had to lick with your tongue your palm so that no fragment would perish. The same question is addressed in the text of St Cyril. The ladies always had to receive with the palm of the hand covered with a white cloth called the dominicale. They had to make the same gesture, to bow deeply, and then immediately receive with the tongue. Then they purified the cloth, the dominicale, so that no fragment would be lost. But even so, the church noticed that some fragments could be lost, and so the church, in the West and in the East, began to put the Holy Sacrament directly in the mouth. This was a natural process of deepening reverence. It was an organic and growing deepening in the faith.