For we [Christians] have had the good news [about resting with God] preached to us, just as the Israelites [had good news proclaimed to them. See 1:16-19]. But the message they heard did not benefit them, because it was not coupled with faith by those who heard it.

So, since it still remains for some people to enter into that rest, but those to whom the good news was previously proclaimed [See verse 2] failed to enter it because of disobedience [See 3:18]