The Name Jesus and also the Name Christ were known from the Beginning, and were honored by the Inspired Prophets
19 But it is a great and convincing proof of his incorporeal and divine unction that he alone of all those who have ever existed is even to the present day called Christ by all men throughout the world, and is confessed and witnessed to under this name, and is commemorated both by Greeks and Barbarians and even to this day is honored as a King by his followers throughout the world, and is admired as more than a prophet, and is glorified as the true and only high priest of God. And besides all this, as the pre-existent Word of God, called into being before all ages, he has received august honor from the Father, and is worshipped as God.
20. But most wonderful of all is the fact that we who have consecrated ourselves to him, honor him not only with our voices and with the sound of words, but also with complete elevation of soul, so that we choose to give testimony unto him rather than to preserve our own lives.
21. I have of necessity prefaced my history with these matters in order that no one, judging from the date of his incarnation, may think that our Saviour and Lord Jesus, the Christ, has but recently come into being.
Source: Church History (New Advent)