Samuel T. Lachs, Rabbinic Commentary, 333 writes:
There are three passages in rabbinic sources which are of note here; but not one combines both the form and the message of this parable. First, one could point to the well-known statement “Some obtain and enter the Kingdom in an hour, while others reach it only after a lifetime.” The idea here is parallel to that of the parable but not its form.
When R. Bun bar R. Hiyya died, R. Ze’ira came in and delivered a eulogy over him: “Sweet is the sleep of the labourer whether he has eaten little or much. It is not written here ‘sleep,’ but whether he has eaten little or much. To what can R. Bun bar R. Hiyya be compared? To a king who hired many laborers and there was one who was more skilled in his work, more [than others]. What did the king do? He walked up and down with him. At evening the laborers came to get their wages and he gave him the same wages as he gave to them. Whereupon they murmmured and said, “We labored the whole day long and this one worked but two hours and he gave him the same as he gave us.’ The king said to them, ‘This one did in two hours more than you did in the entire day.’ Similarly, R. Bun labored in the study of Torah for twenty-eight years and learned what a diligent scholar could learn in a hundred years.” [TJ Ber 2.8, 5c]
... to what can this be compared? To a king who hired two laborers, one of them worked a whole day and received a dinar, and one worked one hour and received a dinar. Which one was more beloved to him [the king]? The one who worked one hour and received a dinar. Similarly, Moses our treacher served Israel for one hundred and twenty years, and Samuel served for fifty-two years, and the two of them were equal before the Omnipresent, as it is said, Then the Lord said to me, “Though Moses and Samuel stood before Me ...” [Jer. 15.1], and likewise it is written, Moses and Aaron were among His priests, Samuel also was among those who called upon His name [Ps. 99.6], and similar to these verses it is said, sweet is the sleep of the laborer whether he has eaten little or much [Koh. 5.11].