John says “the law was given through Moses; grace and truth came through Jesus Christ” (John 1:17) and “from the fullness of his grace we have all received one blessing after another” (1:16). Luke said “all spoke well of him and were amazed at the gracious words [or words of grace] that came from his lips” (Luke 4:22).
However, Jesus Himself rarely used the word charis ("grace"). In the two instances where He did He taught something profoundly important about grace. His teachings were about doing good to others when there is no possibility that they can repay us – doing good to others without expecting to be rewarded for it. Showing grace to others in this way is our response to the grace God has shown us. We cannot earn salvation by good works. We cannot do anything for God which would ever repay what He has done for us. Salvation is God’s gift. So we are to be imitators of God by being gracious (or grace-givers) to others – behaving towards them in a way which imitates (on a small scale) the grace of God to us.
In fact, in Jesus' teachings about the Kingdom He was mainly teaching about grace.
For example, Matthew groups several parables together in a collection of stories beginning with the words “the kingdom of heaven is like …” (Matthew 13). An interesting thing about these parables is that none of them speak specifically about the kingdom as our reward or of a kingdom in the way we might think of one: as a nation or country. In fact, they don’t seem to be speaking about a future kingdom at all, but describing how the kingdom is preached, how it begins, and the characteristics of the people who respond to the kingdom-message, the citizens of the kingdom. In fact, Jesus says almost nothing about the future kingdom after His second coming.
Christadelphianism generally has put the emphasis of the kingdom almost entirely on the future - the final consummation - and ignored almost completely Jesus' teachings about the present reality of the kingdom. In this way Christadelphianism is a "half-gospel" and not a complete picture.