Midrasz do Hioba 1:8

(Numb. 30:3:) “When someone makes a vow (neder) to the Lord.” Let our master instruct us: How are konamot (i.e., vows of abstinence) and vows (nedarim)? Thus have our masters taught (in Ned. 2:1): [If one makes] a konam (i.e., a vow of absitinence) [that he will not sleep, that he will not speak; [if he utters a konam to his wife] “that I will not have marital relations with you,” such a one is liable to [the injunction] (in Numb. 30:3), “he shall not break his word.” [If he swears] an oath (shevu'ah)] that he will not sleep, that he will not walk, he is forbidden [to do so].¹Cf. Ned. 2:2-5; Ned. 13b, 14b-15a; 20a; yNed. 2:2-5 (37b-6); above, Lev. 1:16. Oaths (shevu'ot) carry more weight than vows (nedarim); and vows, than oaths. How so? [if one makes] a konam not to make a sukkah, not to take up a lulab, not to put on phylacteries, in the case of vows (nedarim) it is forbidden to put them on or to make them, even though they are commandments (of the Torah); but in the case of oaths (shevu'ot) it is permitted, because one does not swear to transgress against the commandments. The Holy One, blessed be He, said to Israel, “Be circumspect with your vows (nedarim) and do not break them; for all who break vows (nedarim) end up in being faithless in oaths (shevu'ot).” And the one who is faithless in oaths is denying the Holy One, blessed be He through it and will never have forgiveness, as stated (in Exod. 20:7 = Deut. 5:11), “for the Lord will not exonerate [one who takes His name in vain].” [Yet] it is also written (in Jer. 4:2), “And you shall swear, ‘As the Lord lives,’ [in truth, in justice, and in righteousness].” The Holy One, blessed be He, said to Israel, “Do not think that you have permission to swear in My name even in truth.²Numb. R. 22:1. You are not entitled to swear by My name unless you possess all the following attributes (of Deut. 10:20), “The Lord your God you shall fear, Him you shall serve, to Him you shall hold fast, [and by Him you shall swear]”: That you should be like those three who were called God-fearing, Abraham, Job, and Joseph: Abraham of whom it is written (in Gen. 22:12), “For now I know that you fear [God].” Concerning Job it is written (in Job 1:1), “the man was blameless [and upright, one who feared God].” Concerning Joseph it is written (in Gen. 42:18), “for I fear God.” Ergo (in Deut. 10:20), “The Lord your God you shall fear.” (Deut. 10:20, cont.:) “Him you shall serve.” [You do so,] if you turn [all] your attention to the Torah, fulfill [its] commandments and have no other work (abodah). It therefore is stated (ibid.), “Him you shall serve (rt.: 'bd).” (Deut. 10:20, cont.:) “To Him you shall hold fast.” Can one hold fast to the Divine Presence? Moreover, has it not already been stated (in Deut. 4:24), “For the Lord your God is a consuming fire?” It is simply [being stated with reference to] anyone marrying off his daughter to a scholar who reads [Scripture] and recites [Mishnah], that he engage in commerce³Gk.: pragmateia. for him and have him benefit from his assets.⁴Ket. 111b; cf. Sot. 14a. It is with reference to [such a] one that it is stated (in Deut. 10:20), “to him you shall hold fast.”
If you have all these [attributes] you may swear; if not, you are not entitled to swear. There is a story about King [Jannai], that he had two thousand towns and they all were destroyed because of a true oath. (Numbers 30:17:) “Between a man and his wife, between a father and his daughter.” Just like a man only annuls vows of self-affliction and matters between him and her, so too a father only annuls with regards to self-affliction and what is between him and her.

R. Jochanan said: "What does the passage (Ruth 1, 1) And it came to pass in the days when the judges judged, mean? It was a generation that judged its judges. If the judge said to a person: 'Remove the mote from thy eye,' he answered: 'Take the beam out of thine own eyes.' If the judge said to one: 'Thy silver is become dross,' the answer was: (Is. 1, 32) Thy wine is drugged with water." (Job 1, 6-9) Now it happened … .that the accuser (Satan) also came in the midst of them, etc. Thus said Satan before the Holy One, praised be He! "Sovereign of the Universe! I have sped all over the world and found no trusty man like thy servant Abraham, to whom thou dost say (Gen. 13, 17) Arise, wall: through the land in the length of it and in the breadth of it, for unto thee will I give it. And notwithstanding this, when he searched for a grave to bury his wife Sarah, and did not find one until he bought it for four hundred silver shekels, he did not murmur or bear anything against Thee." Then said the Lord to Satan: "Hast thou directed thy attention toward My servant Job, for there is none like him . . and shunned evil. What does shunned evil, mean? R. Aba b. Samuel said: "Job was liberal with his money; the custom of the world is if a laborer has done some service to the value of a P'ruta that the employer [takes him to the storekeeper] buys something for this coin, and gives the laborer one-half of what is due him. Job, however, gave him the whole coin for such services. R. Jochanan remarked: "That which was said concerning Job is more important than that which was said concerning Abraham, for regarding Abraham it is written (Gen. 22, 12) Now I know that thou fearest God, etc. And regarding Job it is written (Job. 1, 1) And that man was whole-heearted and upright, and one that feared God and shunned evil."

He was righteous (Gen. 6:9). This suggests that he was one of the seven men born circumcised.¹⁰Tradition differs as to the number of men born circumcised. Buber Tanhuma, Noah 6 mentions ten, Midrash on Psalms 9:7 lists thirteen. Adam and his son Seth were born circumcised, as it is written: He begot a son in his own likeness after his image, and he called him Seth (Gen. 5:3). Noah was born circumcised, as it is written: He was righteous (lit. “perfect”) in his generations (ibid. 7:1); Jacob was born circumcised, for it is said: And Jacob was a quiet (lit. “perfect”) man (ibid. 25:27); Joseph was born circumcised, for it is written: These are the generations of Jacob: Joseph (ibid. 37:2) because he resembled his father; Moses was born circumcised, as it is said: And she saw that he was a goodly child (Exod. 2:2); and Job was born circumcised, as it is written: A wholehearted (lit. “just”) and upright (“perfect”) man (Job 1:1).