Standing for Bible readings

Please explain how come sometimes we will stand for the readings during church service and other times we will not. Pastor says, "Out of respect for Jesus' words, please stand." But another reading will be from the Bible, etc. and we will not stand. Thanks!

Christian Worship: Manual, the “handbook” for our hymnal, explains: “The congregation stands for the reading of the Gospel. In the past soldiers put down their weapons and kings removed their crowns when the Gospel was read. Christ—his life, his words of law and gospel, his suffering, his death, his resurrection, his ascension, his assignment to his Church, his promise to return—is the center of the Gospel. The faithful have waited for this moment, this reading. They stand in reverence. ” (pp. 173-174)

Through the gospel lesson Jesus—the Word (John 1), the Word of God (Revelation 19:13)—comes to us. The gospel lesson relays the words and works of Christ. For those reasons, we have retained an ancient practice of showing respect and awe for the Lord and his gospel by standing.

That practice of course falls into the category of adiaphora: those things that God has neither commanded nor forbidden. In Christian freedom we gladly include that posture in our liturgy.