15:5 abideth in me. Certain outward evidences can be observed when one is truly “continuing” in Christ. “He that saith he abideth in Him ought himself also so to walk, even as He walked” (I John 2:6). “Whosoever abideth in Him sinneth not” (I John 3:6). “If ye abide in me, and my words abide in you, ye shall ask what ye will, and it shall be done unto you” (John 15:7). There would be exceptions, of course, for no one is perfect, but these attributes can and should be generally evident in those who are really in Christ.
15:5 can. Here the word “can” here is the Greek dunamai, indicating “have the power to.”