Justifier is one translation of the Greek word dikaiōn. It can also be translated “Him who justifies.” The word indicates a person who shows or declares another person to be righteous. Paul points out that, through Jesus (Yeshua‘), God was in a position to be just by punishing sin, but also to be the One who justifies us because He dealt with our guilt.
Justifier in Greek:
Strong’s Concordance number: 1344
Bible references: Rom. 3:26; 4:5; 8:33
To declare, I say, at this time His righteousness: that He might be just, and the justifier of him which believeth in Jesus. (Romans 3:26 KJV)