Mark 1:15
King James Version
15 And saying,
The time is fulfilled,
and the kingdom of God is at hand:
repent ye,
and believe the gospel.
How do we know it is the last days?
Simple.
SCRIPTURE will tell you.
2 Timothy 3:1-9
King James Version
3 This know also,
that in the last days perilous times shall come.
2 For men shall be lovers of their own selves,
covetous, boasters, proud,
blasphemers, disobedient to parents,
unthankful, unholy,
3 Without natural affection,
trucebreakers, false accusers,
incontinent, fierce,
despisers of those that are good,
4 Traitors, heady, highminded,
lovers of pleasures more than lovers of God;
5 Having a form of godliness,
but denying the power thereof:
from such turn away.
6 For of this sort are they which creep into houses,
and lead captive silly women laden with sins,
led away with divers lusts,
7 Ever learning,
and never able to come to the knowledge of the truth.
8 Now as Jannes and Jambres withstood Moses,
so do these also resist the truth:
men of corrupt minds,
reprobate concerning the faith.
9 But they shall proceed no further:
for their folly shall be manifest unto all men,
as their's also was.
This is what believers of Christ can expect, and must do in these crucial times:
2 Timothy 3:13-17
King James Version
13 But evil men and seducers
shall wax worse and worse,
deceiving,
and being deceived.
14 But continue thou in the things
which thou hast learned and hast been assured of,
knowing of whom thou hast learned them;
15 And that from a child thou hast known the holy scriptures,
which are able to make thee wise unto salvation
through faith which is in Christ Jesus.
16 All scripture is given by inspiration of God,
and is profitable for doctrine,
for reproof,
for correction,
for instruction in righteousness:
17 That the man of God may be perfect,
thoroughly furnished unto all good works.
Related material:
Biblical Prophecy You Will Want To Listen To
Dr. David R. Reagan's "A Prophetic Manifesto"
50 Reasons We Are in the End Times