Rest = Hearing the Gospel and adding faith
Faith = (with the leaning of the entire personality on God in absolute trust and confidence in His power, wisdom, and goodness)
Matt 11:28 Come to Me, all you who labor and are heavy-laden and overburdened, and I will cause you to rest. [I will ease and relieve and refresh your souls.]
Heb 4:1 THEREFORE, WHILE the promise of entering His rest still holds and is offered [today], let us be afraid [to distrust it], lest any of you should think he has come too late and has come short of [reaching] it.
Heb 4:2 For indeed we have had the glad tidings [Gospel of God] proclaimed to us just as truly as they [the Israelites of old did when the good news of deliverance from bondage came to them]; but the message they heard did not benefit them, because it was not mixed with faith (with the leaning of the entire personality on God in absolute trust and confidence in His power, wisdom, and goodness)
Eph 2:8 For it is by free grace (God's unmerited favor) that you are saved (delivered from judgment and made partakers of Christ's salvation) through [your] faith. And this [salvation] is not of yourselves [of your own doing, it came not through your own striving], but it is the gift of God;
Ps 127:2 It is vain for you to rise up early, to take rest late, to eat the bread of [anxious] toil--for He gives [blessings] to His beloved in sleep