A.T. Robertson Commentary Luke 12:10

"And every one who shall speak a word against the Son of man, it shall be forgiven him: but unto him that blasphemeth against the Holy Spirit it shall not be forgiven." — Luke 12:10 (ASV)

But unto him that blasphemeth against the Holy Spirit (τω δε εις το αγιον πνευμα βλασφημησαντ). This unpardonable sin is given by Mr 3:28f.; Matthew 12:31f. immediately after the charge that Jesus was in league with Beelzebub. Luke here separates it from the same charge made in Judea (11:15-20). As frequently said, there is no sound reason for saying that Jesus only spoke his memorable sayings once. Luke apparently finds a different environment here. Note the use of εις here in the sense of "against."