Jesus Christ is truly present in the Eucharist, under the appearances of bread and wine.  The Eucharist is "the source and summit of the Christian life.  The other sacraments, and all ecclesiastical ministries...are bound up with the Eucharist and are oriented towards it"  (Catechism of the Catholic Church, 1324).

How is Christ present in the Eucharist?
Jesus Christ is present in the Eucharist in a unique and incomparable way.  He is present in a true, real and substantial way, with his Body and his Blood, with his Soul and his Divinity.  In the Eucharist, therefore, there is present in a sacramental way, that is, under the Eucharistic species of bread and wine, Christ whole and entire, God and Man (Compendium of the Catechism of the Catholic Church, 282).

What is required to receive Holy Communion?
To receive Holy Communion one must be fully incorporated into the Catholic Church and be in the state of grace, that is, not conscious of being in mortal sin.  Anyone who is conscious of having commited a grave sin must first receive the sacrament of Reconciliation before going to Communion.  Also important... is a spirit of recollection and prayer, observance of the fast prescribed by the Church, and an appropriate disposition of the body (gestures and dress) as a sign of respect for Christ (Compendium of the Catechism of the Catholic Church, 291).
 

Is a Catholic who is divorced and remarried excommunicated?

 The penalty of automatic excommunication was removed by Pope Paul VI in November 1977. However, a divorced and remarried Catholic who has not received a declaration of nullity from the Church regarding a previous marriage or marriages, or who has remarried outside the Church, may not receive the sacraments. A person in this situation is urged to begin the process to request a declaration of nullity as soon as possible to see if this situation can be remedied.

Want to learn more about this wonderful Sacrament of the Eucharist?  Check out the Presence Series on Formed.org!