The first part of this is on watching. Jesus mentioned it often so it must be important for us to do.
 

Jesus told this to His disciples in the garden: Matthew 26:41 Watch and pray, that ye enter not into temptation: the spirit indeed is willing, but the flesh is weak.
"Watch" here means to give strict attention to, be cautious, active, to take heed lest through remission and indolence some destructive calamity suddenly overtake one (Strong's # 1127).

Mark 14:38 Watch ye and pray, lest ye enter into temptation . The spirit truly is ready, but the flesh is weak. (Strong's # 1127).
 
Matthew 24:42 Watch therefore: for ye know not what hour your Lord doth come. (Strong's # 1127).

Matthew 25:13 Watch therefore, for ye know neither the day nor the hour wherein the Son of man cometh. (Strong's # 1127).

Mark 13:33 Take ye heed, watch and pray: for ye know not when the time is.
"Watch" here means to keep awake, be attentive & ready (Strong's #69).
Mr 13:34 For the Son of man is as a man taking a far journey, who left his house, and gave authority to his servants, and to every man his work, and commanded the porter to watch.
Mr 13:35 Watch ye therefore: for ye know not when the master of the house cometh, at even, or at midnight, or at the cockcrowing, or in the morning: (Strong's # 1127).
Mr 13:36 Lest coming suddenly he find you sleeping. Mr 13:37 And what I say unto you I say unto all, Watch. (Strong's # 1127).
"Sleeping" here in Mark 13:36 in the Strong's Concordance # 2518 means: To fall asleep - To yield to sloth and sin - To be indifferent to one's salvation.
 
Luke 12:37 Blessed are those servants, whom the lord when he cometh shall find watching: (Strong's # 1127).
Luke 12:40 Be ye therefore ready also: for the Son of man cometh at an hour when ye think not.
Luke 21:36 Watch ye therefore, and pray always, that ye may be accounted worthy to escape all these things that shall come to pass, and to stand before the Son of man. Watch here means to keep awake, be attentive & ready
(Strong's # 69).

1 Corinthians 16:13 Watch ye, stand fast in the faith, quit you like men, be strong. (Strong's # 1127)

Ephesians 6:18 Praying always with all prayer and supplication in the Spirit, and watching thereunto with all perseverance and supplication for all saints. (Strong's # 69).

Colossians 4:2 Continue in prayer, and watch in the same with thanksgiving. (Strong's # 1127)

1 Thessalonians 5:6 Therefore let us not sleep, as do others; but let us watch and be sober. (Strong's # 1127)
 
2 Timothy 4:5 But watch thou in all things, endure afflictions, do the work of an evangelist, make full proof of thy ministry.
"Watch" here means to be sober, to be calm and collected in spirit - to be temperate, dispassionate, circumspect (Strong's # 3525).
 
1 Peter 4:7 But the end of all things is at hand: be ye therefore sober, and watch unto prayer. (Strong's # 3525).

Revelation 3:2 Be watchful, and strengthen the things which remain, that are ready to die: for I have not found thy works perfect before God. (Strong's # 1127)
Re 3:3 Remember therefore how thou hast received and heard, and hold fast, and repent. If therefore thou shalt not watch, I will come on thee as a thief, and thou shalt not know what hour I will come upon thee. (Strong's # 1127)

Revelation 16:15 Behold, I come as a thief. Blessed is he that watcheth, and keepeth his garments, lest he walk naked, and they see his shame. (Strong's # 1127)

Ezekiel 33:2-8 talks about a watchman who would warn the people when the enemy was coming against them. God told Ezekiel he was the watchman who should warn the people not to sin.
The word "warn" in Ezekiel 33:3 means to admonish, teach, shine, send out light, be light, be shining (Strong's # 2094). God has also called Christians to sound the warning trumpet and tell the people to turn from sin and turn to God.
WATCH
AND
PRAY

Part 1

WATCH