In Holy Scripture, a Name Is Mentioned

The Characteristics of Allah (SWT) in Upanishads

That heavenly person is without body; He is both without and within, not produced, without breath and without mind, pure, higher than the high Imperishable.

 The Upanishads, Part II, Second Mundaka, First Khanda, Verse No. 2, P.34, Publisher: Motilal Banarsidas Pvt. Ltd. New Delhi. 2003 (First published in 1884 by Oxford University Press)

He is very luminous, without form; he is both without and within; unborn, without prana, without mind, pure and greater than great, the indestructible one.

 Know the Upanishads by Ramanuj Prasad, P. 82, Published by Pustak Mahal, Delhi-6. 2003.

And this is almost same, we find about Allah, in Holy Qura'an, under Ch. 112 (Sura: Ikhlas)

1. Qul huwa Allahu ahadun; 2. Allahu alssamadu; 3. Lam yalid walam yooladu; 4. Walam yakun lahu kufuwan ahadun

1. Say: He is Allah, the One and Only; 2. Allah, the Eternal, Absolute; 3. He begetteth not, nor is He begotten; 4. And there is none like unto Him.

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The Holy Prophet (SAWS) in Non-Islamic Holy Scriptures has clearly been mentioned by Name much before his Advent

In Samaveda Sanhita, which is about 1500 B.C. old i.e. 2000 years before Islam.

Ahmed has received deep knowledge of eternal law.

 Samaveda Sanhita, Ch. II, Decade I Verse No. 142

In Bhavashiya Purana, also a very old Hindu Holy Book that dates back about 1500 B.C.

The above Sanskrit Text has been copied from "Shree Bhavishya Maha Puranam" V2, PS.282-283, Published by Nag Publisher, New Delhi, India

A Spiritual teacher, who comes from a foreign country and language (Malechha) will appear with his disciples and his name will be famous as "Mahamad". He will be a dweller in deserts (i.e. Arabia). ...............my follower will be a person circumcised, without a tail (i.e. on the head), keeping beard and will be eating all lawful food and among animals all lawful except swine. These followers will be known as Musalmans. These Muslims will establish themselves Trans-Sindh river.

 Shree Bhavishya Maha Puranam, V2, Prati Sarg, Part III, Verse Nos 5-27 and 31,P.282-283,

In Old Testament (Torah and Dzabur)

In the Ch. Songs of Solomon of the Holy Bible under the Sub-Ch. 5:16 we find the name of Muhammed clearly mentioned in Hebrew:

Hebrew: ḥikwō maməṯaqqîm wəḵullwō maḥămadîm.

English Translation: His mouth is most sweet: yea, he is Mahamadim i.e. Mahamad without im adding to it as in Hebrew im used for respect and added to the noun. For instance, the name of God in Hebrew is "Eloha" but in the Holy Bible it is written with im as a sign of respect to the God i.e. ĕlōhîm (Gen 1:1, 3-4 etc)

 Shir Hashirim in OT Leningrad Codex, Ch 5:16 and Songs of Solomon (Canticles), OT, the Holy Bible (KJV), Ch5:16

In the Gospel of St. Barnabas

And when I saw him my soul was filled with consolation, saying: "O Mohammed, God be with thee, and may he make me worthy to untie thy shoe latchet, for obtaining this I shall be a great prophet and holy one of God."'

 The Gospel of Barnabas, (Tr. By Lonsdale and Laura from Latin in 1907, London, Oxford Edition),Ch.44, Sacrifice of Ishmael,P.45

'And God shall make answer even as a friend who jesteth with a friend, and shall say: "Hast thou witnesses of this, my friend Mohammed?" And with reverence he shall say: "Yes, Lord." Then God shall answer: "Go, call them, O Gabriel." The angel Gabriel shall come to the messenger of God, and shall say: "Lord, who are thy witnesses?" The messenger of God shall answer: "They are Adam, Abraham, Ishmael, Moses, David, and Jesus son of Mary."

 The Gospel of Barnabas, (Tr. By Lonsdale and Laura from Latin in 1907, London, Oxford Edition),Ch.55, Muhammad at the Judgment Day, P.56

God said: 'Wait Mohammed; for thy sake I will to create paradise, the world, and a great multitude of creatures, whereof I make thee a present, insomuch that whoso shall bless thee shall be blessed, and whoso shall curse thee shall be accursed. When I shall send thee into the world I shall send thee as my messenger of salvation, and thy word shall be true, insomuch that heaven and earth shall fail, but thy faith shall never fail." Mohammed is his blessed name.'

 The Gospel of Barnabas, (Tr. By Lonsdale and Laura from Latin in 1907, London, Oxford Edition),Ch.97, P.56

The disciples answered, 'O Master, who shall that man be of whom thou speakest, who shall come into the world?'

Jesus answered with joy of heart: 'He is Mohammed, messenger of God, and when he cometh into the world, even as the rain maketh the earth to bear fruit when for a long time it hath not rained, even so shall he be occasion of good works among men, through the abundant mercy which he shall bring. For he is a white cloud full of the mercy of God, which mercy God shall sprinkle upon the faithful like rain.'

 The Gospel of Barnabas, (Tr. By Lonsdale and Laura from Latin in 1907, London, Oxford Edition),Ch.163, P.163

In Testament of St. John (New Testament)

Vulgate (Latin): Paraclitus autem Spiritus Sanctus, quem mittet Pater in nomine meo, ille vos docebit omnia, et suggeret vobis omnia quæcumque dixero vobis. (John 14:26)

English: But the Comforter, 3875 which is the Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you. (John 14:26)

G3875: παράκλητος, paraklētos that is pronounced as par-ak'-lay-tos and it means in English as: An intercessor,