The Mekhilta DeRabbi Yishmael draws an illuminating comparison between the fear of parents and the observance of Shabbat (the Sabbath). The verse in (Leviticus 19:3) places them side by side: "A man, his mother and his father shall you fear, and My Sabbaths shall you keep." This juxtaposition is not accidental. It is an invitation to compare the rewards.
The reward for keeping Shabbat is spelled out in (Isaiah 58:13-14): "If you keep your feet from dishonoring the Sabbath... then you will find pleasure in the Lord, and I will set you on the heights of the earth." The person who honors Shabbat properly is promised divine pleasure and elevation, being set upon the heights of the earth, a position of spiritual and perhaps material eminence.
By placing fear of parents in the same verse as Shabbat observance, the Torah implies that the rewards are comparable. A person who truly fears their parents, who treats them with the reverence and care the commandment demands, can expect a blessing on the same scale as the one promised for keeping Shabbat.
This is a powerful statement about the weight the Torah places on family obligations. Shabbat is one of the most fundamental institutions in Jewish life, a direct sign of the covenant between God and Israel. To equate parental reverence with Shabbat is to say that honoring the people who brought you into the world is as sacred as honoring the day that God sanctified at creation.