According to the teachings of the Church God is one but in spite of this...
According to the teachings of the Church God is one but in spite of this,the above ‘three persons’ are inseparable because the Trinity is inseparable, however, each part of the Trinity is independent." William M. Miller, a christian scholar, says in this regard: "... These Gospels are not inconsistent with each other! but are complementary. They are like four photographs of one person taken from four different sides.
I know that you are going to ask now, If God is One then how it is possible for Jesus (A.S) to be the Son of God? To answer this question, it must be said that these two issues are secrets, which their understanding dose not seem reasonable, of course, in our limited intelligence. The rationalistic inability is obvious in the above issue and thus we should discuss the issue of the Trinity in another place. Here, we just refer to a Quranic verse in this regard: " O’ People of the Book!
overstep not in your religion, and say not upon God except the Truth; Verily; Verily, the Messiah Jesus(A.S), son of Mary, is only an apostle of God and His Word which He conveyed unto Mary, and a Spirit (proceeding) from Him; Believe therefore in God, and His apostles, and say not (that there are) three (gods); Desist! It is good for you; Verily, Verily, God! (there is) only One God!
Far be it from His (Absolute)-purity that there be for Him a son; His is whatever is in the Heavens and whatever is in the Earth; God is sufficient as a Protector.(An-Nisa, 171) The Jesus (A.S)'s Nativity according to the Holy Quran A part of Surah Maryam describes the Jesus (A.S)'s Nativity as follows: "And mention in the Book (Quran) about Mary (also) when she withdrew herself from her family (in the house) eastward, then she took a veil (coverherself) from them; then sent We unto Our Spirit, then he (the Spirit) appeared unto her a man sound (in form).
Said she: " Verily I fly for refuge in The Beneficent (God) from thee, (be gone from me) if thou art God-fearing." Said he:" I am only a messenger (Angel) of thy Lord: so that I give to thee a son purified".
Said she: " How can there be unto me a son while hath not touched me (any) man and nor was I unchaste!" Said he: " So shall it be; thy Lord sayeth, It is easy for Me, and that We will make him a sign (miracle)(of Ours) unto the people and a Mercy from Us; It is a matter (already) decreed." So she conceived him and retired with him (away from her people) to a remote place.