John 12:50
And I know that his commandment is life everlasting: whatsoever I speak therefore, even as the Father said unto me, so I speak. And I know that his commandment is life everlasting: whatsoever I speak therefore, even as the Father said unto me, so I speak.
Jesus cried out with intense desire that people receive the truth and live. He did not speak from Himself, but the Father who sent Him gave Him a commandment telling Him what He should say and what He should speak. Whatever He spoke He spoke exactly as the Father told Him, so His words carry the Father's authority.
He knew the Father's commandment is life everlasting, revealing the way to eternal life. He came as the light of the world so that whoever believes in Him will not remain in darkness. Believing in Him is believing in the Father who sent Him.
He came not to judge the world but to save it, yet people are judged by the light that has shone on their pathway. Those who reject Him and do not receive His words will be judged in the last day by the word He spoke, so receiving His truth brings light and eternal life while rejecting it brings darkness, judgment, and eternal death. Devoted Christians who died keeping Sunday while cherishing and walking in all the light given in their day are not lost and will not be denied salvation, because people are not accountable for light that never came to them.
Greater, clearer light is now given, including increased light on the Sabbath, so this generation must improve its privileges and opportunities, advance step by step with Jesus, and search the Scriptures as truth constantly unfolds. Refusing this light after Christ has spoken leaves no excuse for sin and no cloak for it. His obedience to the Father is an example for His followers, who must learn from Him and do what He tells them.