If all we had to go on was the Sermon on the Mount, we could reconstruct much of the Gospel, especially its view of how to live well. Running through it is the thread of here-and-now living.
It begins in the Beatitudes with the “are” (present tense) verbs. The blessed life is meant for here and now, not there and later. The grace to live abundantly is never deferred, it is offered to us moment by moment. 
Once we link into Jesus’ opening remarks, we see the theme extending through the rest of the Sermon. The “are” verbs continue, and there is not a single admonition that cannot be experienced in the present moment. And when he concluded the sermon, Matthew is sure to let us know that his words had an immediate effect on those who heard him (Matthew 7:28-29). It is one way his gospel says, “The teachings of Jesus can have an immediate effect on you too.”
And that is the motif which runs through all of Jesus’ teachings and ministry. “The Kingdom of heaven IS…”. His parables can be applied here-and-now. “Go and do likewise” is counsel for current reality. Abundant living is in the present moment.
The other way we see this is in Jesus’ healing ministry, which is not only an expression of his compassion, but also an indication that God is concerned about what is happening to us right now, right here. Restoration and renewal may be perfected in the new creation, but they are begun here-and-now.
But something more is happening. John writes in his gospel of seven “I am” statements that Jesus made about himself.  Not only are these an indication of his oneness with the Father (harking back to the “I AM” name of Yahweh we have already noted), they are also John’s way of telling his readers that the One who is “full of grace and truth” (John 1:14) offers that fullness to us in the present moment, and Jesus’ final promise nails everything down, “I am…with you always” (Matthew 28:20).
With all this, and more, revealed to us it is no wonder that Jesus summarized abundant life in three words: “abide in me” (John 15), another present-tense invitation from which life (inward and outward) emerges. And this is why life “in Christ” is the essence of the Christian life. 
It is for reasons like this that many theologians believe Christology is the lens through which to read Scripture. I agree, and a major reason I do is because when I read the Bible through the incarnate Jesus and the excarnate Christ, I am invited to receive, apply, and express the Message here-and-now.
 E. Stanley Jones, ‘The Christ of the Mount’ (Abingdon Press, 1931). This is the best book I have found for connecting the Sermon on the Mount to present-moment living.
. The seven “I am” statements are found in John 6:35, 8:12/9:5, 10:7, 10:11, 11:25, 14:6, and 15:1.
 E. Stanley Jones, ‘In Christ’ (Abingdon Press, 1961). Using the page-a-day style, Jones gives us the opportunity (if we wish) to spend a year exploring the “in Christ” life. A transforming read.