Isaiah 59:16,17 - He put on righteousness as His breastplate

59:16

“God saw that there was no one”. Now consider this. The previous verse has said that God looked and was displeased. So what was His response? Was it that therefore He needed to send judgement upon the people? No, it was that He needed someone to save the people. This is what Jesus meant when He said in John 3:17 God did not send Him into the world to condemn the world. The common misunderstanding is that this means Jesus did not come to tell us we were sinners, or that any of our actions or ways are wrong. This is nonsense. God does tell us that we are wrong, Jesus did, it is part of the work of the Holy Spirit. But He does this not so that he can have a full charge sheet against us, but so that we will repent, turn to Him and receive forgiveness. But God was appalled, for there was no one on the earth who could intervene on our behalf to rescue us. So what did God do? Did He give up and then send the judgement that we deserve? No! Instead “His own arm achieved salvation for Him”. God sent His Son to save us. We are saved through the righteousness of the Son of God, Jesus Christ.

59:17

There are some echoes of the armour of God, spoken of in Eph 6:10-17. Righteousness is His breastplate, and salvation His helmet. We tend not to fully appreciate the righteousness involved in God’s salvation. This is one of the reasons why those who deny penal substitutionary atonement do so. There are many aspects to the cross, but one of the key ones is that God has acted justly, our sin and our sinfulness has been fully dealt with. There is no charge that can be brought against us (Rom 8:33). It is not just that God loves us, it is also that from a legal or righteousness standpoint, our sin has been completely dealt with (and doing this was an act of love!). Those who deny the penal substitutionary atonement aspect of the cross do not fully appreciate the extent and depth of God’s love.

God also “put on the garment of vengeance”. In the immediate context this involved the defeat of the Assyrians and later the Babylonians. More generally, God will and does act against sin and evil.