"65.1 N o Sanctification Without Obedience I have met many who claimed to live without sin. But when tested by God's word these persons were found to be open transgressors of His holy law. The clearest evidences of the perpetuity and binding force of the fourth commandment failed to arouse the conscience. They could not deny the claims of God, but ventured to excuse themselves in breaking the Sabbath. They claimed to be sanctified, and to serve God on all days of the week. Many good people, they said, did not keep the Sabbath. If men were sanctified, no condemnation would rest upon them if they did not observe it. God was too merciful to punish them for not keeping the seventh day. They would be counted singular in the community should they observe the Sabbath, and would have no influence in the world. And they must be subject to the powers that be. SL 66"
"He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him."
The EGW passage directly connects the claim of knowing God with obedience to His commandments, mirroring the principle stated in 1 John 2:4. The specific example of Sabbath observance further strengthens the connection.