With regards to the description of ‘Eesaa ‘alaihissalaam being described as “His Word which He conveyed to Maryam”[1]  the Shaykh Muhammad ibn Saalih al ‘Uthaymeen rahimahullaah states:

Allaah applied the (term) “Word” to him because he ‘alaihissalaam was created by means of a word. So the hadeeth is not taken upon its apparent (literal) meaning, since ‘Eesaa ‘alaihissalaam was not a word because he used to eat and drink and pass urine and open his bowels. And all the (usual) human situations would occur to him.

Allaah, the Most High, states:

Indeed the example of ‘Eesaa with Allaah is just as the example of Aadam. He (Allaah) created him from dust then He said to him, “Be!” and he was.
Soorah aale ‘Imraan (3) aayah 59

 And ‘Eesaa ‘alaihissalaam was not the Word of Allaah because the Speech of Allaah is an Attribute existing with Him and not separate and distinct from Him.

As for ‘Eesaa, then he was a being separate and distinct from Allaah subhaanahu ; he would come and go and eat food and drink.

(Al qawl ul mufeed (1/73) of Shaykh Muhammad ibn Saalih al ‘Uthaymeen rahimahullaah, translated by Nasser ibn Najam)

[1] Hadeeth reported by Al Bukhaaree (4453) and Muslim (28)

With regards to the use of the singular at times and the plural at other times in Allaah’s addressing the people in the Qur-aan, Shaykh Muhammad ibn Saalih al ‘Uthaymeen rahimahullaah states:

And the address in the aayah is to the Prophet sall Allaahu ‘alaihi wa sallam but He said:

<<Wa qadaa rabbuka allaa ta’budoo illaa iyyaahu…>>

meaning:

<<And your (in the singular form) Lord has decreed that you (in the plural form) worship none except Him alone…>>
Soorah al Israa (17) aayah 23

And He did not say, that you (singular) worship none.

And the like of this in the Qur’aan is His statement, He the Most High:
<<O Prophet, when you (in the plural form) divorce the women…>>
Soorah at Talaaq (65) aayah 1

Therefore the first address is to the Messenger sall Allaahu ‘alaihi wa sallam and the second is general (to the people).  So what is the benefit behind this changing of the manner (of addressing)?

1) To draw attention, because getting the attention of the person being addressed is something desired by the one speaking. And this occurs here by changing the manner (of addressing).

2) That the Prophet sall Allaahu ‘alaihi wa sallam was the leader of his nation. And the address directed to him was directed to all of his nation.

3) An indication that whatever the Messenger sall Allaahu ‘alaihi wa sallam is addressed with, then it is for him and for his nation – except for something where there is a proof that it is specifically for him.

4) And in this aayah in particular, there is an sign that the Prophet sall Allaahu ‘alaihi wa sallam was one who was under the control of the Lord, and not (himself) a Lord and Nurturer - a servant, and not one who is to be worshipped.  So he comes under His statement:

<<…that you (in the plural form) worship..>>

And sufficient for him in nobility is that he be a servant of Allaah, the Mighty and Majestic.

(Al qawl ul mufeed (1/32 to 33) of Shaykh Muhammad ibn Saalih al ‘Uthaymeen rahimahullaah)

The scholar  Abdur Rahmaan ibn Nasir as Sa’dee rahimahullaah said about the statement of Allaah, the Most High:

<<No fruit emerges from its covering nor does any female become pregnant nor give birth to offspring except by His knowledge.
And on the Day when He will call them, “Where are My partners?” they will say, “We inform you that none of us bears witness.”>>
(Soorah al Fussilat (41) aayah 47

So no fruit emerges from any tree except that He is has detailed knowledge of it.

…nor does any female become pregnant – from the children of Adam, or other than them from the different types of animals, except with His knowledge.

nor give birth to offspring except by His knowledge – so how can the people of shirk equate with Him, He the Most High,  that which has no knowledge nor hearing nor seeing?

And on the Day when He will call them – meaning those people who make shirk with Him, on the Day of Resurrection, rebuking (them) and making manifest their lie. So He will say to them:

Where are My Partners? – those whom you claimed were My partners, such that you worshipped them, and argued over that, and showed enmity to the Messengers on account of them?

they will say – affirming the falsity of taking them (the false deities) as objects of worship and partners along with Allaah

We inform you that none of us bears witness – meaning we inform you, O our Lord, and bear witness upon us, that not one of us testifies that taking them as objects of worship and partners was something correct. So now all of us go back to (believing in the) falsity of worshipping them, and we declare ourselves free of them.

(Tafseer ul Kareem ir Rahmaan  of as Sa’dee rahimahullaah, translated by Nasser ibn Najam)

 The scholar  Abdur Rahmaan ibn Nasir as Sa’dee (died 1376 AH (1955 CE))rahimahullaah said about the saying of Allaah, the Most High:

<<All praise is for Allaah, the Rabb of all the Worlds.>>
(Soorah al Faatihah (1) aayah 1)

“the Rabb (Lord and Nurturer) of all the Worlds” – and His tarbiyyah (nurturing) of His creation, He the Most High, is of two types: general and specific.

So the general type is His creating the creation and giving them provision and guiding them to that which contains benefits for them, that which allows them to survive in this worldly life.

And the specific type is His tarbiyyah of His beloved and dutiful servants; so He nurtures them with true faith and He grants them the success to attain it, and He completes it for them. And He repels away from them those things which act as diversions and impediments and obstructions between them and it.

And its reality is that it is tarbiyyah of being granted success in attaining every good and protection from every evil.

(Tayseer ul Kareem ir Rahmaan  of as Sa’dee rahimahullaah p39,  translated by Nasser ibn Najam)