Including the words of Allah, may He be exalted, about His Prophet Moosa {peace be upon him), {[he] said, “My Lord, indeed I am, for whatever good You would send down to me, in need”} in du‘aa’ asking for one’s needs to be met
Question

What is the meaning of the verse, {“My Lord, indeed I am, for whatever good You would send down to me, in need”}? Is it permissible to include it with supplications to have one’s needs met?
Praise be to Allah.Allah, may He be exalted, tells us about Moosa (peace be upon him), when he fled from Pharaoh and his people, and reached Madyan (interpretation of the meaning):
{And when he directed himself toward Madyan, he said, “Perhaps my Lord will guide me to the sound way.”
And when he came to the well of Madyan, he found there a crowd of people watering [their flocks], and he found aside from them two women driving back [their flocks]. He said, “What is your circumstance?” They said, “We do not water until the shepherds dispatch [their flocks]; and our father is an old man.” 
So he watered [their flocks] for them; then he went back to the shade and said, “My Lord, indeed I am, for whatever good You would send down to me, in need”} [al-Qasas 28:22-24].
{And when he directed himself toward Madyan} which was south of Palestine, where Pharaoh had no authority
{he said, “Perhaps my Lord will guide me to the sound way”} that is, the straightforward way to reach it, with ease and with no trouble or difficulty. So Allah showed him the right way, and he arrived in Madyan.
{And when he came to the well of Madyan, he found there a crowd of people watering [their flocks]} – they were people who had a lot of livestock
{and he found aside from them} that is, standing apart from that group of men
{two women driving back [their flocks]} from the water troughs, because they could not reach them due to the crowd of men, and the men were too mean and ill-mannered to water their flocks for them.
Moosa said to them: {He said, “What is your circumstance?”} that is, why are you standing aside?
{They said, “We do not water until the shepherds dispatch [their flocks]} that is, usually we cannot water our flocks until the shepherds move on with their flocks, then when there is no one there, we water our flocks.
{and our father is an old man} that is, he has no strength to water the flocks, and we have no physical strength ourselves to do it, and we have no menfolk who could push past the shepherds.
Moosa (peace be upon him) felt sorry for them and felt compassion towards them, {So he watered [their flocks] for them} without asking for any payment in return; he had no intention except seeking the pleasure of Allah, may He be exaltede. After he had watered the flocks for them, at a time of intense heat in the middle of the day, as is indicated by the phrase {then he went back to the shade}, he sat down to rest in the shade after having exerted himself.
{and said} in that situation, seeking provision from his Lord: {“My Lord, indeed I am, for whatever good You would send down to me, in need”} that is, I am in need of whatever good You may send down to me and make easy for me. Making this implicit request is more eloquent than asking explicitly." (Tafseer as-Sa‘di  p. 614).
Ibn ‘Aashoor (may Allah have mercy on him) said:
When he rested after pulling up buckets full of water and watering the flock of the two women, pushing his way through many shepherds to have a turn, and he felt the coolness of the shade, this blessing reminded him of previous blessings that Allah had bestowed upon him, such as saving him from being killed, granting him wisdom and knowledge, saving him from the consequences of killing the Egyptian, and enabling him to reach a land that was populated by a great nation, after crossing deserts, wilderness and barren lands. He remembered all of that whilst enjoying the coolness of the shade and resting after working hard. Hence he uttered some concise words of gratitude, praise and supplication all at the same time:
{“My Lord, indeed I am, for whatever good You would send down to me, in need”}.
His words {“indeed I am, for whatever good You would send down to me, in need”} were an expression of gratitude for previous blessings.
His words {“indeed I am, for whatever good You would send down to me, in need”} were an expression of praise to Allah, for He is the giver of good.
The best thing to happen to a stranger is for him to find shelter where he can eat and sleep, and a wife in whom he can find comfort.
Allah answered his prayer by prompting Shu‘ayb to send for him, invite him to stay with him, and give his daughter to him in marriage, as is indicated by the conjunction fa’ (translated here as “then”) in the verse {Then one of the two women came to him walking with shyness} [al-Qasas 28:25], which indicates that this happened immediately afterwards." (At-Tahreer wa’t-Tanweer  20/102).
These words on the part of Moosa (peace be upon him) were implicitly asking of Allah, merely expressing his need before his Lord, rather than asking in explicit terms.
This is like the words of Ayyoob (peace be upon him): {Indeed, adversity has touched me, and you are the Most Merciful of the merciful} [al-Anbiya’ 21:83].
And the words of Yoonus (peace be upon him): {There is no god worthy of worship except You; exalted are You. Indeed, I have been of the wrongdoers} [al-Anbiya’ 21:87].
Shaykh al-Islam Ibn Taymiyah (may Allah have mercy on him) said:
Thus he described his situation as being in need of whatever good Allah would send down to him. This is an implicit way of asking Allah to send down goodness to him." (Majmoo‘ al-Fataawa (10/244).
Ibn Katheer (may Allah have mercy on him) said:
Asking may be done by telling the situation of the one who is asking, and his need, as Moosa (peace be upon him) said: {“My Lord, indeed I am, for whatever good You would send down to me, in need”}." (Tafseer Ibn Katheer 1/136).
This could only be understood as a kind of beseeching Allah and demonstrating humility and need before his Lord, for he knows that he is in need of his Lord and that He is able to make him independent of means so that he has no need of anyone except Him. Hence he beseeches Him by virtue of his need for Him and the fact that He has no need of His creation and has the power to help him.
Shaykh al-Islam Ibn Taymiyah (may Allah have mercy on him) said:
To speak of one’s need and desperation in an implicit manner is more eloquent than explaining it explicitly, although that [i.e., asking explicitly] is clearer in terms of stating what you seek." (Majmoo‘ al-Fataawa 10/246).
There is nothing wrong with the Muslim reciting these words when asking to have his needs met, because he is beseeching Allah, may He be exalted, by virtue of his need for Him. In that case, the person is describing his situation and acknowledging that Allah is independent of means and is able to help him. This way of beseeching is appropriate for one who seeks what Allah has of goodness and blessings.
Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) said:
The fifth type – that is, of the types of beseeching Allah that are prescribed in Islamic teachings – is: beseeching Allah, may He be exalted, by mentioning one situation. In other words, the one who is offering supplication beseeches Allah, may He be exalted, by describing his situation and his need. One example of that is the words of Moosa (blessings and peace of Allah be upon him): {“My Lord, indeed I am, for whatever good You would send down to me, in need”}. Here, he was beseeching Allah, may He be exalted, by mentioning his situation, asking Him to send down goodness to him." (Majmoo‘ Fataawa wa Rasaa’il al-‘Uthaymeen 2/337).
And Allah knows best.