Isaiah 58:3,13-14 (ESV)
3 ‘Why have we fasted, and you see it not? Why have we humbled ourselves, and you take no knowledge of it?’ Behold, in the day of your fast you seek your own pleasure, and oppress all your workers.
13 “If you turn back your foot from the Sabbath, from doing your pleasure on my holy day, and call the Sabbath a delight and the holy day of the Lord honorable; if you honor it, not going your own ways, or seeking your own pleasure, or talking idly;
14 then you shall take delight in the Lord, and I will make you ride on the heights of the earth; I will feed you with the heritage of Jacob your father, for the mouth of the Lord has spoken.”
This is evidently a rebuke against selfish pleasure, but the lack of concrete examples in the chapter makes the concept a little bit vague to me. What is exactly meant by "seeking/doing one's own pleasure" in Isaiah 58? I'm especially interested in understanding how this selfish pleasure can simultaneously be the reason why fasting becomes ineffective (verse 3) and the Sabbath is broken (verses 13 and 14).