The Blessing of Incense at High Mass

At High Mass the Priest places incense into the thurible and pronounces the following blessing:

AB illo The sign of the cross.benedicaris, in cujus honore cremaberis. Amen.

BE thou The sign of the cross.blessed by Him in Whose honour thou shalt be burned.  Amen.

The Incensing of the Altar at High Mass

The Priest then incenses the Blessed Sacrament (if it is exposed), or the crucifix, the relics of the saints (if they are exposed) and then the entire altar.  He returns the thurible to the Deacon (or at Sung Mass, to the server) who then incenses the Priest.