Here are some quotations from Non-Muslim writers over the past few centuries -
T.W. Rhys Davids, Nineteenth century Professor:
There is every reason to believe that the Pitakas [sacred books containing the legends of Buddha] now extant in Ceylon are substantially identical with the books of the southern canon, as settled at the Council of Patna about the year 250 B.C. As no work would have been received into the Canon which were not then believer to be very old, the Pitakas may be approximately placed in the forth century B.C. and parts of them possibly reach back very nearly, if not quite to the time of Gautama (Buddha) himself.
Samuel Beal, Nineteenth century:
We know that the Fo-pen-hing was translated into Chinese from Sanskrit (the ancient language of Hindstan) so early as the eleventh year of the reign of Wing-ping (Ming-ti) of the Hans Dynasty, ie., 69 or 70 A.D. We may, therefore, safely suppose that the original work was in circulation in India for sometime previous to this date. These points of agreement with the Gospel narrative arouse curiosity and require explanation. If we could prove that they [the legends of Buddha] were unknown in the East for some centuries after Christ, the explanation would be very easy. But all the evidence we have goes to prove the contrary....
Ernest de Bunsen, Nineteenth century:
With the remarkable exception of the death of Jesus on the cross and of the doctrine of atonement by vicarious suffering, which is absolutely excluded by Buddhism, the most ancient of the Buddhisitic records known to us contain statements about the life and doctrines of Gautama Buddha whic h correspond in a remarkable manner and impossibly by mere chance with the traditions recorded in the Gospels about the life and doctrines of Jesus Christ...
Max Muller, Nineteenth century Professor:
Between the language of Buddha and his disciples, and the language between Christ and his apostles, there are strange coincidences. When some of th e Buddhist legends and parables sound as if taken from the New Testament, though we know that many of them existed before the beginning of the Christian era.
Kenneth Scott Latourette, Twentieth century:
Approximately five centuries older than Christianity, by the time of the birth of Christ, Buddhism had already spread through out much of India and Ceylon and had penetrated into Central Asia and China.
M. LAbbe Huc, Nineteenth century:
The miraculous birth of Buddha, his life and instructions, contain a great number of the moral and dogmatic truths professes in Christianity.
T.W. Doane, Nineteenth century:
...nothing now remains for the honest man to do but acknowledge the truth, which is that the history of Jesus of Nazareth, as related in the books of the New Testament maybe a copy of that of Buddha, with a mixture of mythology borrowed from other nations.
Both Buddha and Jesus were baptized in the presence of the spirit of G-D.
Both went to their temples at the age of twelve, where they are said to have astonished all with their wisdom.
Both supposedly fasted in solitude for a long time: Buddha for 47 days and Jesus for 40.
At the conclusion of their fasts they both wandered to a fig tree.
Both were about the same age when the began their public ministry: When he [Buddha] went again to the garden he saw a monk who was calm, tranquil, self-possessed, serene, and dignified. The prince determined to become such a monk, was led to make the great denunciation. At the time he was 29 years of age....Jesus when he began his ministry, was about thirty years of age... Luke 3:23
Both were tempted by the devil at the beginning of their ministry: To Buddha, he said: Go not forth to adopt a religious life but return to your kingdom, and in seven days you shall become emperor of the world, riding over the four continents. To Jesus he said: All these [kingdoms of the world] I will give you, if you fall down and worship me. Matt 4:9 Buddha answered the devil: Get away from me Jesus responded ...begone Satan! Matt 4:10.
Both experienced the supernatural after the devil left: For Buddha: The skies rained flowers, and delicious odors prevailed in the air. For Jesus ..angels came and ministered to him. Matt 4:11.
The multitudes required a sign from both in order that they might believe.
Both strove to establish a kingdom of heaven on earth.
Buddha represented himself as a mere link in a long chain of enlightened teachers. Jesus said: Think not that I have come to abolish the law and the prophets; I have come not to abolish them but to fulfill them.Matt 5:17.
According to the Somadeva (a Buddhist holy book), a Buddhist ascetic's eye once offended him, so he plucked it our and cast it away. Jesus said 'If your right eye causes you to sin, pluck it out and throw it away;...' Matt 5:29.
Buddha taught that the motive of all our actions should be pity of love of our neighbor. Jesus taught: ...love your enemies and pray for those who persecute you.... Matt 5:4.
Buddha said: Hide your good deeds and confess before the world the sins you have committed. Jesus said: Beware of practicing your piety before men to be seen by them;...Matt 6:1 and Therefore confess your sins one to another and pray one for another, that you may be healed... James 5:16.
Both are said to have known the thoughts of others: By directing his mind to the thoughts of others, [Buddha] can know the thoughts of all beings. But Jesus, knowing their thoughts, said: Why do you think evil in our hearts? Matt 9:4.
Both were itinerant preachers with a close group of trustees within a larger group of disciples.
Both demanded that their disciples renounce all worldly possessions.
Both sent their disciples on missionary assignments: The number of disciples rapidly increased and Gautama sent forth his monks on missionary tours hither and thither, bidding them wander everywhere, preaching the doctrine, and teaching men to order their lives with self -restraint, simplicity, and charity. And Jesus called to him twelve apostle and began to send them out two by two....So they went out and preached that men should repent. Mark 6:7,
Both had a disciple who walked on water: To convert skeptical villagers, Buddha showed them his disciple walking across a river without sinking. He said: Come So Peter got out of the boat and walked on the water and came to Jesus but when he saw the wind, he was afraid, and beginning to sink he cried out: Lord save me! Matt 14:29-30. 21. One day Ananda, the disciple of Buddha, after a long walk in the country, meets with Matangi, a woman of the low caste of the Kandalas, near a well, and asks her for some water. She tells him what she is, and that she must not come near him. But he replies: My sister, I ask not for your caste of your family, I ask only for a draught of water. She afterwards became a disciple of Buddha. There came a woman of Samaria to draw water. Jesus said to her give me a drink. For his disciples had gone away into the city to buy food. The Samaritan woman said to him: How is it that you a Jew, ask a drink of me, a woman of Samaria? For Jews have no dealings with Samaritans. John 4:7-9
Both men received similar receptions: The people swept a pathway, the gods strewed flowers on the pathway and branches of the coral trees, the men bore branches of all manner of trees and the Bodhisattva Sumedha spread his garments in the mire, and men and gods shouted All hail. And they brought the colt to Jesus mad threw their garments on it, and he sat on it. And many spread their garments on the road and others spread leafy branches which they has cut from the fields. Mark 11:7 -8.
When Buddha died: The coverings of [his] body unrolled themselves and the lid of his coffin was opened by supernatural powers. When Jesus dies: And behold, there was a great earthquake; for an angel of the L-RD descended from heaven and came and rolled back the stone and sat upon it. Matt 28:2
In the year 217 B.C. Buddhist missionaries were imprisoned for preaching; but and angel, genie or spirit came and opened the prison door, and liberated them. They arrested the apostles and put them in the common prison. But at night an angel of the L-RD opened the prison doors and brought them out. Acts 5:18-19.
Both men's disciples are said to have been miracle workers.