By me - By my instruction and merits.
Shall be saved - See John 5:24.
Shall go in and out ... - This is language applied, commonly to flocks. It meant that he shall be well supplied, and defended, and led “beside the still waters of salvation.”
Related Commentaries of John 10:9
John 10:9
9 I am the door: by me if any man enter in, he shall be saved, and shall go in and out, and find pasture.