Jesus Taught and practiced mystical (or Yogic) Communion with the Spirit of God (or the Spirit That IsGod). As reported in the third chapter of the "Gospel of John," Jesus said to Nicodemus: "You must be born from above. Unless a man is born from above, he cannot see the Kingdom of God." What is born of the flesh IS flesh. What is born of the Spirit IS Spirit.That is to say, Jesus Taught the religion of God AS Spirit, or the religion of Salvation (or God-Realization) through descent (or fourth state reception) of the Spirit, ego-transcending (fourth-to-fifth stage) mystical ascent via the Spirit, and (fifth stage) mystical Absorption In the Spirit.
The physical Ascension of Jesus did not happen - because one does not (and cannot) get to "Heaven" (or to God) by physically flying up into the physical sky! But (even in accordance with the New Testament reports) it can be surmised that Jesus did Realize a Spiritual Ascension. The true Christian (and non-Christian) Ascension is the fourth-to-fifth stage mystical ascent to the brain core (and the "sky" of mind) via the "ladder" (or the "cross") of the nervous system (in the line of the spinal column).
The only real and possible Ascension is the fifth stage Spiritual journey (or ascent) to God (or to the "Heaven" of Yogic Realization of "Cosmic Consciousness," and Yogic God-Union), but, among the ancients, only the Initiates (or the Spiritual elite) knew this. Jesus may rightly be surmised to have been such an Initiate. Therefore, the stories of his Resurrection and Ascension can be rightly understood only as popular (or exoteric) retellings (or reformulations) of the Initiate experiences and Teachings of Jesus, the spiritual experiences of his "Inner Circle," and the esoteric (or symbolic) language of the general ancient tradition of mysticism. (And, apart from such an esoteric, or mystical, interpretation, the stories of Jesus' Resurrection and Ascension no longer make any sense at all.)