This instruction is given not only to the apostles but to the whole church throughout all the gospel age. All Christians must live with the expectation of Christ’s return. That is the event which will make sense of all we do. We evangelise, we feed the flock, we baptize, we meet for the Lord’s Supper: all this, because Christ is coming again. We do not want him to come at a time when we have grown less serious about his return, or started to live as if life now is what matters. The health of the Christian life is measured in terms of how much we are conscious that we live for his return.
In Matthew’s Gospel it goes further with this picture. After a long time, it says, he returns. So there is going to be a long gap between the fall of Jerusalem in A.D. 70 and the final return of the Lord, but it cannot be far off now. We know that preachers in the 18th century said this, and in the 19th century, and certainly in the 20th. Here we are in the 21st century – what is new? Well, a tremendous amount is new in the now militant atheism, which is overthrowing society and increasingly seeking to do so, from the 1960s abortion act, the constant throwing down of God-given moral standards, the pressing of sexual activity onto the youngest of people, the legalising of homosexuality. These are just a few among so many indications of a vicious and active rejection of God, an imposition of these anti-values on society. We have never seen things like this before.