ציטירנדיקער פּירוש אויף בראשית 17:5

והיה כי תבא אל הארץ אשר נשבע ה' לאבותנו, “it will be when you come to the land which the Lord has sworn to our forefathers to give to us;” basing themselves on the above line, the Mishnah in bikkurim chapter 1,4, concludes that a proselyte who offers the first ripe products of his orchard while allowed to offer them, must refrain from reciting the benediction which includes thanking the Lord for having given the land to “our fathers”, seeing that he had not been Jewish at that time. Nonetheless he is commanded to address the Lord our G–d in his prayers as “our G–d and the G–d of our fathers.” The reason for this ruling is that the Jerusalem Talmud in tractate bikkurim 1,4, has ruled that all converts are called descendants of Avraham, seeing that G–d had told him that he would become the “father of a multitude of nations.” (Genesis 17,5)

Someone offering his bikkurim may have his servant carry same while he is on the way to Jerusalem as far as the Temple Mount. Once he reaches that mount, he must place them on his own shoulder and carry them forthwith. This ruling applies even to the king. The recital of the passage from the Torah has to take place while the basket with the fruit is still on his shoulder. When he reaches the words (verse 10) “the earth which You have given to me,” he may deposit the basket, take hold of it with his hand, and the priest will then place his hand beneath his own and begin the weaving motion.
If someone does not own any soil (farmland) but has bought a tree and wishes to offer the first fruit ripening on his tree he may do so without reciting the “confessional” (the term refers clearly to the passage from verse 5-10). This is because if he were to speak of the fruit of “his” soil he would make a liar of himself. A proselyte also may not recite the relevant passage seeing he cannot acknowledge that his forefathers cried out to the Lord while enslaved in Egypt (verse 7). There is an opinion in the Talmud according to which such a proselyte may recite the relevant passage seeing that Avraham is perceived as being the “father” of all proselytes. The author of that opinion cites as proof that G’d said to Avraham (Genesis 17,5) “here I have made you the father of a multitude of nations.” This means that Avraham is the adopted father of all those who decide to take shelter under the benevolent wings of the Shechinah (convert to Judaism). Maimonides adopts this interpretation as halachically valid (Hilchot Bikkurim 4,3). Perhaps we may even detect a hint in the language of the text that proselytes may recite the passage, seeing that the Torah writes: “you as well as the proselyte and the Levite in your midst.” (verse 11) This appears to show that the Torah treats all three categories of Jews mentioned in that verse as equal in respect to the bikkurim legislation.
Priests and Levites who have planted orchards within their cities in the outer rim reserved for gardens, etc., are subject to he law of bikkurim in every respect of that law. This is why the Torah wrote: “you as well as the Levite.” In the olden days the rule was that farmers who were able to read Hebrew would recite the passage unassisted, whereas those unable to read Hebrew would have it read for them and they would repeat it. It was found that as a result of this practice farmers who were illiterate would cease bringing their bikkurim to save themselves embarrassment. The Rabbis therefore decreed that the passage is to be read before everyone who brings bikkurim and will be repeated word by word by the farmer in order to save the illiterate farmers any possible embarrassment. (Maimonides Hilchot Bikkurim 3,11) This practice was similar to the practice nowadays not to allow individuals to read the passage from the Torah to which they have been called up so as not to put to shame those who are unable to read it by themselves.

שאינו יכול לומר "אשר נשבע לאבותינו לתת לנו" – Since his ancestors were not from Israel and converts did not take a portion in the land. But Maimonides wrote that the Halakha is not like this Mishnah; rather, the convert brings [the First Fruits] and recites [Deuteronomy 26:5-10] and is able to say, “to our fathers to assign us” (Deuteronomy 26:3), because the Land was given to Abraham and he was the father of converts, as he was for Israel, as it states (Genesis 17:5): “for I make you the father of a multitude of nations.” But we [the Rabbis] expound upon it {Berakhot 13a): “In the past, you were the father of Aram; now you are the father of the entire world.” And similarly, when he [the convert] prays, whether on his own or in the synagogue, he says, “the God of our fathers” even if his mother was not an Israelite.