90 Finally, there are those who assert that our prayers should be directed not to the person of Jesus Christ, but rather to God, or to the Eternal Father through Christ, since our Savior as Head of His Mystical Body is only "Mediator of God and men." But this certainly is opposed not only to the mind of the Church and to Christian usage, but to truth. For to speak exactly, Christ is Head of the universal Church as He exists at once in both of His natures moreover He Himself has solemnly declared: "If you shall ask me anything in my name, that I will do." For although prayers are very often directed to the Eternal Father through the only-begotten Son, especially in the Eucharistic Sacrifice - in which Christ, at once Priest and Victim, exercises in a special manner the office of Mediator - nevertheless not infrequently even in this Sacrifice, prayers are addressed to the Divine Redeemer also; for all Christians must clearly know and understand that the man Jesus Christ is also the Son of God and God Himself. And thus, when the Church Militant offers her adoration and prayers to the Immaculate Lamb, the Sacred Victim, her voice seems to re-echo the never-ending chorus of the Church Triumphant: "To him that sitteth on the throne and to the Lamb benediction and honor and glory and power forever and ever."
Source: Mystici Corporis Christi (Vatican.va)