After Mass, the priest sometimes places the Sacred Host in a beautiful golden vessel called a monstrance. We can see Jesus in His Eucharistic Presence. This special time for prayer and adoration is called Exposition of the Blessed Sacrament.
Some parishes have Exposition every day and every night. This is called perpetual adoration. It is both a wonderful privilege and a great responsibility to have Exposition. Someone must be before the Eucharistic Presence at all times. It would be a grave irreverence to leave Jesus unattended during Exposition.

God grants great graces during periods of Exposition. It is through silence and intimacy with Christ that our interior life develops. We learn to love Him more deeply. We learn to listen attentively to Him. (Psalm 45:11, Be still and know that I am God.) The Sacred Host exposed in the monstrance reminds us of those moments during the Mass when the Holy Eucharist is visible, at the elevation after the Consecration, the showing of the broken Host prior to Communion, and the moment of our Communion when the priest presents the Sacred Host to us.

During adoration, we speak to Jesus as our God and as our closest friend. We tell Him our joys and our troubles. We ask for His forgiveness and His help and we thank Him for His great goodness to us. Eucharistic adoration flows from the celebration of the Eucharist and leads back to a greater appreciation of the Holy Sacrifice. "Eucharistic adoration prolongs and increases the fruits of our communion in the Body and Blood of the Lord." Ecclesia de Eucharistia Pope John Paul 11.

Source: Christine McCarthy (In Memory of Me.)
Imprimatur Cardinal George Pell  Archbishop of Sydney.