Luke 22:39-46 (KJV)

39 And he came out, and went, as he was wont, to the mount of Olives; and his disciples also followed him.

40 And when he was at the place, he said unto them, Pray that ye enter not into temptation.

41 And he was withdrawn from them about a stone’s cast, and kneeled down, and prayed,

42 Saying, Father, if thou be willing, remove this cup from me: nevertheless not my will, but thine, be done.

43 And there appeared an angel unto him from heaven, strengthening him.

44 And being in an agony he prayed more earnestly: and his sweat was as it were great drops of blood falling down to the ground.

45 And when he rose up from prayer, and was come to his disciples, he found them sleeping for sorrow,

46 And said unto them, Why sleep ye? rise and pray, lest ye enter into temptation.

Here we discover more about prayer. The 1st word that stood out was “accustomed (was wont)”. We have to have make prayer a custom, that is regular at a place set aside for it. In the Lord’s Prayer Matthew 6:13 (KJV) And lead us not into temptation, but deliver us from evil: For thine is the kingdom, and the power, and the glory, for ever. Amen.
It also tells us the same. In time of great difficulty we need to pray more fervently that we may not enter into temptation. Our flesh can be even weaker, the devil and his demons are very active. Judas entered into temptation and it cost him everything. 
Like Jesus prayed there are times when what we want and God’s will are in opposition. Jesus knew God’s will but asked for it to be changed to avoid what He knew will happen. In these times we need to surrender it all to Jesus and keep praying with even greater intensity. The Lord Himself will send His angels to strengthen us so that we can continue in the path the Lord set before us. We can see according to verse 45 that at times of sorrow sleep can overcome us. Jesus advised His disciples to get up. It is easier to fall asleep when tired by laying or sitting down. When we are tired it is best to be in an uncomfortable position for prayer like kneeling or standing. Being disciplined in prayer helps us to be better prepared to resist temptation. Jesus said to Paul in 2 Corinthians 12:9 “My grace is sufficient for you, for My strength is made perfect in weakness.”