Yesterday’s reading regarding the sending away of the mother bird (Deut 22:6-7) gives us insight into the nature of Torah. The sending away of the mother bird is considered the “least of the commandments.” We fulfill all of the mitzvot, rather than only the “greater” ones because we do not know the reward for any of the mitzvot, save two (actually three…see Deut 11:20,21) the “least” and the “greatest.” And they both carry the same reward. Here are some texts to illustrate the point.
R. Abba b. Kahana said: The Holy One, blessed be He, said: ‘Do not spend time weighing up the precepts of the Torah, as Scripture hath it, And weighed the mountains in scales- [Based on the word ba-peles] (Isa. 40:12); and do not say, ‘Seeing that this precept is a great one, I will perform it because its reward is great, and seeing that the other precept is a minor one, I will not perform it.’ What did God do? He did not reveal to His creatures the reward for each separate precept, so that they may perform all the precepts without questioning. Whence this? For it is said, ‘Her ways wander, that thou canst not know them.’ It is as if a king hired for himself labourers and brought them straight into his garden without disclosing what he intended to pay for the various kinds of work in the garden, lest they should neglect the work for which the pay was little for work for which the pay was high. In the evening he called each one in turn and asked him: ‘ At which tree have you worked? ‘ He replied: ‘At this one.’ Thereupon the king said to him: ‘This is a pepper tree and the pay for working at it is one golden piece.’ He then called another and asked him: ‘At which tree have you worked? ‘ And he replied: ‘ Under this tree.’ The king thereupon said: ‘This is a white-blossom tree and the pay for working at it is a half a golden piece.’ He then called yet another, and asked him: ‘At which tree have you worked?’ And he replied: ‘At this one.’ Whereupon the king exclaimed: ‘ This is an olive tree and the pay for working at it is two hundred zuz.’ Said the labourers to the king: ‘You should have informed us from the outset which tree had the greater pay attached to it, so that we might have worked at it.’ Thereupon the king replied: ‘ Had I done this, how would the whole of my garden have been worked?’ So God did not reveal the reward of the precepts, except of two, the weightiest and the least weighty. The honouring of parents is the very weightiest and its reward is long life, as it is said, Honour thy father and thy mother, that thy days may be long (Ex. XX, 12); and the sending away of the mother bird is the least weighty, and what is its reward? Length of days.
—Devarim Rabba 6:2
“For the kingdom of heaven is like a master of a house who went out early in the morning to hire laborers for his vineyard. After agreeing with the laborers for a denarius a day, he sent them into his vineyard. And going out about the third hour he saw others standing idle in the marketplace, and to them he said, ‘You go into the vineyard too, and whatever is right I will give you.’ So they went. Going out again about the sixth hour and the ninth hour, he did the same. And about the eleventh hour he went out and found others standing. And he said to them, ‘Why do you stand here idle all day?’ They said to him, ‘Because no one has hired us.’ He said to them, ‘You go into the vineyard too.’ And when evening came, the owner of the vineyard said to his foreman, ‘Call the laborers and pay them their wages, beginning with the last, up to the first.’ And when those hired about the eleventh hour came, each of them received a denarius. Now when those hired first came, they thought they would receive more, but each of them also received a denarius. And on receiving it they grumbled at the master of the house, saying, ‘These last worked only one hour, and you have made them equal to us who have borne the burden of the day and the scorching heat.’ But he replied to one of them, ‘Friend, I am doing you no wrong. Did you not agree with me for a denarius? Take what belongs to you and go. I choose to give to this last worker as I give to you. Am I not allowed to do what I choose with what belongs to me? Or do you begrudge my generosity?’ So the last will be first, and the first last.”
—Matthew 20:1-16, ESV
Rabbi [Judah the Prince] said: …Be as scrupulous about a light precept as of a weighty one, for you do not know the reward allotted for each precept.
Ben Azzai said: Be eager to fulfill the smallest mitzvah and flee from transgression; for one mitzvah induces another and one transgression leads to another transgression. The reward of a mitzvah is a mitzvah, the reward of one transgression is another transgression.