If a priest is to preach the Gospel or Homily and he is not the presiding minister, it is customary for him to receive a blessing from the president if the president is his ecclesiastical superior. This could be the case among fellow priests - a Pastor and a Vicar, or a Prior and a (priest) Monk/Friar/Brother. If the president and preacher are of equal standing (or if the preacher is of higher standing than the president) then there is no such blessing.
This echoes the blessing that the priest received from his Bishop or Religious Superior when first ordained to go out and proclaim the Gospel. If a priest takes the pulpit in place of his superior, he typically obtains the superior’s blessing.
During the Liturgy of the Word, the concelebrants remain at their places, sitting or standing whenever the principal celebrant does.
When the Alleluia is begun, all rise, except for a Bishop, who puts incense into the thurible without saying anything and blesses the Deacon or, in the absence of a Deacon, the concelebrant who is to proclaim the Gospel. However, in a concelebration where a Priest presides, the concelebrant who in the absence of a Deacon proclaims the Gospel neither requests nor receives the blessing of the principal celebrant.
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