A.T. Robertson Commentary 2 Peter 2:15

"forsaking the right way, they went astray, having followed the way of Balaam the [son] of Beor, who loved the hire of wrong-doing;" — 2 Peter 2:15 (ASV)

Forsaking (καταλειποντες). Present active participle of καταλειπω (continually leaving) or καταλιποντες (second aorist active), having left.

The right way (ευθειαν οδον). "The straight way" of 1 Samuel 12:23 (cf. Matthew 7:13f. for this use of οδος), "the way of truth" (2:2).

They went astray (επλανηθησαν). First aorist passive indicative of πλαναω, like Mr 12:24.

The way of Balaam (τη οδω του Βαλααμ). Associative instrumental case after εξακολουθησαντες, for which verb see 1:16; 2:2. These false teachers, as shown in verse 13, followed the way of Balaam, "who loved the hire of wrong-doing" (ος μισθον αδικιας ηγαπησεν).