1. Disrespect of others nullifies service to the deity

    Real love and devotion is accepted by the Lord. Many valuable foodstuffs may be presented to a person, but if the person is not hungry, all such offerings are useless for him. Similarly, we may offer many valuable items to the Deity, but if we have no real sense of devotion and no real sense of the Lord’s presence everywhere, then we are lacking in devotional service; in such a state of ignorance, we cannot offer anything acceptable to the Lord.

    From Srila Prabhupada’s purport to SB 3.29.24