Thank you for your question and for contacting Ask About Islam.
To answer your question, we need to first of all understand what sin is.
What is Sin?
From the Christian point of view, sin is a state of being. It is not a matter of choice for us; it is human nature to sin.
They believe that we inherit the Original Sin committed by our Parents, Adam and Eve, in primordial time.
To Muslims, sin is the deliberate violation of a divine commandment, and humans are answerable for it because they choose to sin despite their ability to avoid it.
For Christians it is absurd for humans to judge or even consider Jesus’ nature as to whether it is sinful or pure. Indeed, for them Jesus is sinless, as he is God, and isn’t it ridiculous to say that God is sinful?
The Nature of All Humans
Controversy arises when Christian apologists claim that the Muslim position on Jesus, peace be upon him, as regards his ‘sinless’ state ought to be the same as the Christian one.
But to a Muslim, human nature at birth is fitrah, i.e the state of innate goodness. No one is born a sinner. All are basically and intrinsically pure. In other words, all are born ‘Muslims’ (those who willingly submit to God’s laws).
Our God-given nature demands that they do not deviate from it.
But as humans are gifted with choice and free will in this world, they may be seduced from their inherent nature of goodness and fall into sin.
In that case, Divine Guidance still helps them to remain true to their original status of intrinsic goodness. Their pure nature does not change.
All are accountable for what they earn, and in the ultimate reckoning each gets the credit or the blame for what he or she has done by his or her own willful choice.
Jesus, According to Islam
For Muslims Jesus is not God; he was only a prophet of God. And this belief is true to the original Abrahamic (Semitic) tradition of pure monotheism.
Indeed, Christians cannot consider Jesus to be God without violating the First Commandment:
The Lord our God, the Lord is one. (Deuteronomy 6:4)
You shall have no other gods before me. (Exodus 20:3)
When asked what the most important command to follow was, Jesus said:
The most important one is this: ‘Hear, O Israel: The Lord our God, the Lord is one. Love the Lord your God with all your heart and with all your soul and with all your mind and with all your strength.’ (Mark 12:29, 30)
Jesus never claims or pretends to be God as we are often asked to believe. He was a great prophet of God; and Muslims always acknowledge his importance as one of the nearest to God:
Behold! the angels said: ‘O Mary! Allah gives you glad tidings of a Word from Him: his name will be Christ Jesus, the son of Mary, held in honor in this world and the Hereafter and of (the company of) those nearest to Allah.’ (Quran 3:45)
Jesus Was a Human Prophet
In short, Jesus was a human prophet. And, as a human, he had a human nature.
The Quran’s repetition of his name as ‘Jesus, son of Mary’ is a strong negation of the Christian claim that he was the Son of God: The son of Mary ought to be fully human.
The Christian claim that Jesus was fully human and fully divine should leave us with two separate beings: one divine and the other human, which is absurd.
The attempt of the Christian apologists to foist a ‘divine’ sinless status upon the Muslim Jesus is, to put it mildly, unreasonable.
But key here is the fact that Islam sees all prophets as infallible as regards intentional, active sin, not because they were divine, but because God created them with a super-human ability to resist sin. They made mistakes, they got angry, but they did not sin.
Jesus, peace be upon him, is included in this lot.
But, let’s talk about this from a Christian perspective.
Sharon Houk answered this question quite well in her article, Did Jesus Really Live a Sinless Life?
It seems impossible for any person to live a sinless life as even the smallest wrongdoing would disqualify us from the “sinless” category. We are correct in concluding it is impossible for a person to be sinless, unless that person was also God.
Later, she says:
The Bible teaches that he grew in maturity, he knew hunger, he knew thirst, he needed sleep, and, eventually he died. He was a complete and perfect man who had physical limitations like all humans have. The difference, however, is that he was born of a woman, but supernaturally conceived of God.
The only problem Islam would have with this statement can be found in the last part of the quote: “…that he was born of a woman, but supernaturally conceived of God.”
In order to convincingly present the doctrine that Jesus was fully human and fully God, the theologians had a hard time. The idea that Jesus was “supernaturally conceived of God” is another way of saying that Jesus was “the only begotten of God”—begotten, not created.
The Absurdity of Dual Nature
The inherent proneness of humans toward sin is of a piece with all the weak characteristics of humans mentioned in the quote above. And that would mean that Jesus being fully human had a tendency to sin.
However, their reply is that he is fully divine too! Fully human and fully divine! The contradiction in language reflects the contradiction in the concepts involved.
Muslims believe that Jesus was a human who was protected by God from falling into serious sins, like all other prophets were. Any mention of a special purity of Jesus refers to his perfectly ascetic character, which kept him free from sexual lust for instance.
And God knows best.
InshaAllah this answers your question.
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