1 Timothy 2, 1 states:

I exhort therefore, that, first of all, supplications, prayers, intercessions, and giving of thanks, be made for all men;

It is God's will and purpose that all men should be saved.

Romans 8, 26 says:

Likewise the Spirit also helpeth our infirmities: for we know not what we should pray for as we ought: but the Spirit itself maketh intercession for us with groanings which cannot be uttered.

In Luke 4, we read that the disciples ask Jesus to teach them how to pray.

In Matthew 17 it says the apostles countenances are changed by prayer.

Prayer can change our countenance.

The motive of prayer is to be found in God's presence. The purpose of prayer is to change us.

Psalm 142 (David's prayer):

[1] I cried unto the LORD with my voice; with my voice unto the LORD did I make my supplication.

[2] I poured out my complaint before him; I shewed before him my trouble.

[3]When my spirit was overwhelmed within me, then thou knewest my path. In the way wherein I walked have they privily laid a snare for me.

[4]I looked on my right hand, and beheld, but there was no man that would know me: refuge failed me; no man cared for my soul.

[5] I cried unto thee, O LORD: I said, Thou art my refuge and my portion in the land of the living.

[6] Attend unto my cry; for I am brought very low: deliver me from my persecutors; for they are stronger than I.

[7] Bring my soul out of prison, that I may praise thy name: the righteous shall compass me about; for thou shalt deal bountifully with me.

Sometimes we go into prayer hoping God will chnage things but we often find that God changes us instead.

The method Jesus taught us in regards to prayer is to ask, seek, and knock; not demand.

In 1 Timothy 2, 1 we read that prayer consists of asking for supplication, intercession, and giving of thanks. Supplication is asking God to help us. Intercession is helping our brethren. When we intercede for others, we remember James 5, 16: