After their return from Babylon in 538 B.C., the people encountered many difficulties. They had a hard time reconciling their difficulties with the promises of the prophet regarding the restoration of the city and its temple (Isaiah 44:28), the population explosion (Isaiah 49:19-21; 54:1-3), the wealth that would become theirs (Isaiah 45:14), and the homage they would receive from other nations (Isaiah 49:22-23). Instead, they encountered delays in the rebuilding of their temple (Ezra 4:1-5), bad economic conditions as the result of natural catastrophes (Haggai 1:6, 9-11; 2:16-17), and the payment of tribute to Persia (Nehemiah 5:15). The transition period was difficult for the people. Many became disillusioned. It was against this background that the prophet proclaimed the messages recorded in these chapters.
Everyone Who Keeps God’s Law Welcomed in His Temple
Who was welcomed in God’s Temple?
Verses 1 and 2 stress the importance of obedience. The prophet exhorted the people to demonstrate their obedience to God in four areas:  “Preserve justice,”  “do righteousness,”  keep the sabbath, and  keep their “hand from doing any evil.” Those who abided by this standard were welcome in God’s Temple.
Verses 3-8 address the issue of whether or not foreigners and eunuchs would be allowed to participate in worship. The eunuchs were probably Jews who had been mutilated while in exile so that they could be trusted to work in royal palaces. Foreigners were non-Jews who became proselytes.
Isaiah declared that both eunuchs and foreigners were welcome to participate in worship as long as they met the requirements outlined in verses 4 and 6:  keep the Sabbath,  choose what pleases God,  keep His covenant, and  love the Lord. (Read Romans 2:29 and Galatians 3:28-29).
Condemnation of Those Who Learned Nothing from the Exile
Who in the postexilic community did the prophet condemn?
Isaiah condemned Judah’s religious and political leaders who had failed to learn anything from the exile (56:9-12). The “watchmen” were the nation’s prophets. Isaiah characterized them as being blind, knowing nothing, being like dumb (mute) dogs unable to bark, interested only in indulging their sinful appetites. The “shepherds” (political leaders) of the nation were no better. They too, were interested only in their own gain. Verse 12 records one of the comments (perhaps a drinking song) of the leaders.
Practical Consideration: What we keep will keep us in or out of trouble.
The prophet gave the people specific instructions regarding God’s expectations of them. God expected His people to keep justice, righteousness, the Sabbath, and their hand from doing any evil. Even eunuchs and foreigners who kept these things would be welcome in God’s Temple. Failure to keep these things however, would keep people in trouble with God.
Isaiah 57:1-2 express alarm at the fact that people were indifferent to the death of righteous and devout men. Verses 3-13 are addressed to those who kept clinging to idolatry, in spite of the experience of the exile. Much of the blame for this can be put on the religious and political leaders who failed to provide godly leadership (56:9-12).
God summoned the idolaters to draw near to hear the charges against them (57:3). Those charges included: blasphemous mockery (57:4), cultic prostitution (57:5a, 7-8), child sacrifice (57:5b), the offering of sacrifices (57:6), and the paying of homage to idols by trusting in the kings of other nations who worshiped them (57:9).
Verse 10 describes the state of those addicted to idolatry. They were tired of it but not enough to forsake it. Verses 11-13 stress the futility of trusting in anything or anyone other than God.