The end why God has given us His laws, is obedience. The written word. To seem to be zealous, if it be not according to the word, is not obedience, but will-worship. Though we serve God with weakness, it may be with willingness. You love to see your servants go cheerfully about their work.
Willingness is the soul of obedience.
God sometimes accepts of willingness without the work, but never of the work without willingness. Obedience must be devout and fervent. Quae ebullit prae ardore. The glorious angels, who, for burning in fervour and devotion, are called seraphim, are chosen by God to serve Him in heaven. The snail under the law was unclean, because a dull, slothful creature.