Here Amos emphasizes the need to seek out God and God alone. Nothing else within our religious life can be a substitute for the seeking after God. Being a follower of Jesus should entail spiritual disciplines and a discipleship that is serious and consistent. But nothing can substitute for seeking after God. Our desire to do God's will and to be in God's grace needs to be the priority in our life. Nothing can replace our desire to be a follower of Jesus.
We see in this passage the repetition of the phrase: "Seek the Lord and live..." What does seeking the Lord look like? Well, for sure we can tell you what it doesn't look like. It isn't trampling on the poor, it is speaking the truth, it isn't taking bribes and using your power to extend your own desires, it is keeping silent. He follows seek the Lord with seek good so that you may live. God is good, we know, that, all the time.
He then transitions to those who would be complacent and pretty self confident in their status before the Lord. Who of us looks forward to the day of the Lord? He says be careful, because we think the day of the Lord is the day that we will be reunited with Jesus, but in fact the day of the Lord will be darkness and not light, it will be gloom with no brightness in it. Our complacency could be our downfall.