Jamieson, Fausset and Brown on 1 Peter 2:6

6. Wherefore also--The oldest manuscripts read, "Because that." The statement above is so "because it is contained in Scripture."

Behold--calling attention to the glorious announcement of His eternal counsel.

elect--so also believers (1Pe 2:9, "chosen," Greek, "elect generation").

precious--in Hebrew, Is 28:16, "a corner-stone of preciousness." See on Is 28:16. So in 1Pe 2:7, Christ is said to be, to believers, "precious," Greek, "preciousness."

confounded--same Greek as in Ro 9:33 (Peter here as elsewhere confirming Paul's teaching. See Introduction; also Ro 10:11), "ashamed." In Is 28:16, "make haste," that is, flee in sudden panic, covered with the shame of confounded hopes.