Mark 16:15-20

He who believes and is baptized will be saved; but he who does not believe will be condemned.

Statue of Saint Mark Apostle and Evangelist – Patriarchal Cathedral Basilica of Saint Mark in Venice

And he said to them, “Go into all the world and preach the gospel to the whole creation. He who believes and is baptized will be saved; but he who does not believe will be condemned.

And these signs will accompany those who believe: in my name they will cast out demons; they will speak in new tongues; they will pick up serpents, and if they drink any deadly thing, it will not hurt them; they will lay their hands on the sick, and they will recover.”

So then the Lord Jesus, after he had spoken to them, was taken up into heaven, and sat down at the right hand of God.

And they went forth and preached everywhere, while the Lord worked with them and confirmed the message by the signs that attended it. Amen.

What do the Fathers say?

Pope St GREGORY the Great. But perhaps some one may say in himself, I have already believed, I shall be saved. That is only true, if he keeps his faith by works; for that is a true faith, which does not contradict by its deeds what it says in words. But there follows: He that does not believe shall be damned.

Pope St Gregory explains the signs that will accompany those who believe:-
Are we then without faith because we cannot do these signs? No, but these things were necessary in the beginning of the Church, for the faith of believers was to be nourished by miracles, that it might increase.
Thus we also, when we plant trees, pour water upon them, until we see that they have grown strong in the earth; but when they have firmly fixed their roots, we stop irrigating them.
These signs and miracles have other things which we ought to consider more minutely. For Holy Church does every day in spirit what then the Apostles did in body; for when her Priests by the grace of exorcism lay their hands on believers, and forbid the evil spirits to dwell in their minds, what do they, but cast out devils?
And the faithful who have left earthly words, and whose tongues sound forth the Holy Mysteries, speak a new language;
they who by their good warnings take away evil from the hearts of others, take up serpents;
and when they are hearing words of pestilent persuasion, without being at all drawn aside to evil doing, they drink a deadly thing, but it will never hurt them;
whenever they see their neighbours growing weak in good works, and by their good example strengthen their life, they lay their hands on the sick, that they may recover.
And all these miracles are greater in proportion as they are spiritual, and by them souls and not bodies are raised.

We have seen in the Old Testament that Elijah was taken up into heaven. But the ethereal heaven is one thing, the aerial is another. The aerial heaven is nearer the earth, Elijah then was raised into the aerial heaven, that he might be carried off suddenly into some secret region of the earth, there to live in great calmness of body and spirit, until he return at the end of the world, and pay the debt of death.
We may also observe that Elijah mounted up in a chariot, that by this they might understand that a mere man requires help from without. But our Redeemer, as we read, was not carried up by a chariot, not by angels, because He who had made all things was taken up by His own power.
We must also consider what Mark subjoins, And sat at the right hand of God, since Stephen says, I see the heavens opened, and the Son of Man standing at the right hand of God. Now sitting is the attitude of a judge, standing of one fighting or helping. Therefore Stephen, when toiling in the contest, saw Him standing, whom he had for his helper; but Mark describes Him as sitting after His assumption into heaven, because after the glory of His assumption, He will in the end be seen as a judge.

St Mark

An extract from St Jerome’s ‘On Illustrious Men’

Mark the disciple and interpreter of Peter wrote a short gospel at the request of the brethren at Rome embodying what he had heard Peter tell. When Peter heard this,he approved it and published it to the churches to be read by his authority.

So, taking the gospel which he himself composed, he went to Egypt and first preaching Christ at Alexandria he formed a church so admirable in doctrine and continence of living that he constrained all followers of Christ to his example.

Philo, seeing the first church at Alexandria, wrote a book on their manner of life under the learned Mark,as something creditable to his nation telling how the believers had all things in common as they had at Jerusalem .

He died in the eighth year of Nero and was buried at Alexandria.

Sources:

Quotes of the Fathers from Thomas Aquinas’ Catena Aurea Translated by St John Henry Newman

St Jerome’s ‘On Illustrious Men’ on Newadvent.org