English Explanation of Pirkei Avot 2:4

He used to say: do His will as though it were your will, so that He will do your will as though it were His. Set aside your will in the face of His will, so that he may set aside the will of others for the sake of your will.
Hillel said: do not separate yourself from the community, Do not trust in yourself until the day of your death, Do not judge not your fellow man until you have reached his place. Do not say something that cannot be understood [trusting] that in the end it will be understood. Say not: ‘when I shall have leisure I shall study;’ perhaps you will not have leisure.
The first half of this mishnah contains another statement by Rabban Gamaliel, the son of Rabbi Judah Hanasi. The second half of the mishnah returns to the statements of Hillel, whose statements were already taught in the previous chapter. The reason that the mishnah goes back to Hillel, is that he was the teacher of Rabban Johanan ben Zakai, whose statements are taught beginning in mishnah eight. The interruption of Hillel’s statements was done in order to bring all of the patriarchs from Hillel’s line together.
One way of understanding Rabban Gamaliel’s statement is that a person should do God’s will with such fervor that it is as if it is his own will. In that way a person’s will will be done for him by God. The first half of Rabban Gamaliel’s statement deals with positive commandments, those which a person “does” and the second half, “set aside your will” etc., deals with negative commandments, those things that a person should refrain from doing. A person should negate his own desires before the commandments given by God. In this way God will protect him against the evil designs of other people. The last half of this statement can also be understood as referring in a respectful way to God. That is to say, God will annul God’s own will to punish human beings, if that human being performs God’s will. Understood in this way, the overall message is one of the unity of the divine and human will. As one commentator (Rabbi Jonah) said, “There should be no distinction between the will of the Holy One, blessed be He, and one’s own will. Both should be the same.”
Do not separate yourself from the community. Hillel’s first statement means that a person should join the community for both its celebrations and for its trials and tribulations. This also has been understand as the reason for praying together as a community. For when one prays by himself, he might ask for things that are detrimental to some. But the community only prays for things which are of benefit to everybody. A reed on its own is easily broken but a bundle of reeds standing together cannot be broken even by the strongest winds.
Do not trust in yourself until the day of your death: do not be sure of your righteousness until the day of your death, for a person can lose a lifetime of merit by doing the wrong things at the end of his life. This lesson is learned from John Hyrcanus, the high priest from the Hasmonean dynasty who at the end of his life became a Sadducee.
Do not judge not your fellow man until you have reached his place: just as you cannot be sure of your own merits, all the more so you can not be sure of the merits and liabilities of your fellow. You do not know what you would do were you in his situation. A clever interpretation of this statement offered by the Meiri is that if one sees a person outside of his city and you find him full of extraordinary virtues, do not conclude that this is his true personality. You can only judge his character by seeing if he acts the same way in “his place”.
Do not say something that cannot be understood [trusting] that in the end it will be understood: a person should make his words clear from the outset, and not speak or write in an unclear manner. Although in the end the matter might be cleared up, in the meanwhile the listener might make mistakes.
Say not: ‘when I shall have leisure I shall study;’ perhaps you will not have leisure: this is similar to the statement that Hillel made in chapter one, mishnah fourteen, “if not now, when?” A person cannot delay studying Torah, saying that he will never have the opportunity to learn. Thus Shammai stated, “make your Torah study a fixed practice” despite your being extremely busy.