One approach to life is to use whatever means possible to achieve our ends.  The psalmist tells us that this is not the way and that we should not copy people who do this, even if they seem to be achieving great success.  Nor should we envy them their seeming success or worry when we are not doing as well.  Those who use underhand and selfish methods tend not to last. Their wealth and success is temporary and has no lasting substance. We must make the choice of leading out lives with integrity and we can relax about doing this, because we know God.

The alternative: do the right thing and trust that God will provide what we need.  He will see us settled in whatever way of life is right for us.  When we trust in him we are spiritually safe, if not totally safe and secure in material things. Safe pasture give the impression of a place of security where good food is in abundance.  Trust in God results in spiritual security and constant spiritual feeding from God when we enter into a relationship with him.

New Bible Commentary, p 509.  enjoy safe pasture (NIV), or 'tend faithfulness', cultivate being faithful (to God and his way) like a shepherd tends his flock

Here is a promise from God - to give us the desires of our heart.  Does this mean that God will give us everything we ask for?  If we 'delight' in him, we will want to please him.  We will try to make our desires the things that he would want too.
John 15: 7 tells us that Jesus said, 'If you dwell in me, and my words dwell in you, ask what you will, and you shall have it.'

In our self-centredness, we tend to look at the last part of this sentence.  Having whatever we ask for seems like a wonderful dream.  But, there's a twist.  God will give us the desires of our heart after we have placed our faith in God and are setting out to delight in him.  When we manage to do this, we will start wanting the same things he does as he begins to change our hearts, minds, attitudes and dreams into his own.

Each translation or paraphrase is a little different - and each helps to make the verses clearer.  ( Praise you, Lord, for people who can take your word and help us to understand it better.)

So that our hearts'desires will be according to God's heart's desires, we must commit our whole life - everything we do every moment of every day - to him.  Making that commitment sounds easy.  It's just a decision - isn't it?  But keeping up the commitment isn't so easy.

When we get married, we make a commitment to another person, to be their best friend and companion, to care for them and share our lives with them, for the rest of our life.  At first, in the 'honeymoon' stage, that seems easy.  We have 'stars in our eyes'.  Our partner seems almost perfect.  Then real life kicks in!  We begin to see each other's faults.  We begin to see that both of us are really commited first to ourselves.  We don't always see things the same way.  We want different things for our lives.  We don't always agree.  We get on each other's nerves. Sometimes we fight and argue and hurt each other.  Now....what about that commitment?

When we get a new job, we make a commitment.  We agree that we will go to work at certain times and be there until an agreed time.  We agree that we will complete certain tasks for our employer and in return he/she will pay us an agreed amount.  We are excited about this new venture.  It's all a novelty.  We look forward to going to work, meeting new work-mates, doing our job and getting satisfaction from it.  And, of course, we look forward to that first pay day!  But sooner or later, things are not perfect at work.  Pressures of work build up, we are asked to work extra hours, new things may be added to our job, a work-mate offends us, the boss tells us off.  We wake up one day after a heavy night out and feel too tired to go to work.  What about our commitment?

Keeping a commitment involves perseverance - stickability.  It sometimes requires us to be flexible, understanding of other people, even forgiving!  Not easy.  It involves sometimes being willing to do things we don't enjoy - to put ourselves out.

Committing ourselves to God is just as hard.  The only difference is that in this case we are committing ourselves to someone who is perfect, who loves us totally and unconditionally.  We are committing ourselves to someone who is absolutely wise and powerful, so we can be confident that when he asks something of us, it will be the right thing to do - and it will be for our own advantage in the long run.  He will never let us down!  We are committing ourselves to someone we can trust absolutely.

This psalm was written by King David.  He had been chosen by God, through the prophet Samuel, to be king of Israel when he was only a young boy.  He knew his destiny.  But there were years of waiting, sometimes at teh court of the current king, a spiritually tortured man who sometimes did good things, but had moved away from God and was led to evil.  David had to wait through years of being pursued by Saul, who knew that David had been appointed by God and was jealous. Saul tried on many occasions to have David murdered.

It was a long wait for David.  He had committed himself to obey God, but he couldn't bring about God's plan - he had to wait for God to do it.  He had to trust that the way God worked would be the right way.

Sometimes we think we understand a plan God may have for us - or a ministry he wants us to undertake.  But nothing seems to be going right. We get impatient and our natural response is to try to organise things to happen ourselves.  That is when disaster can strike.  We have to wait for God's time.  He is the one who knows all the angles.  He is the only one who understands the full picture.  But patience is difficult.

The only way we can continue to be patient is to bring our impatience into the presence of God.  We must tell him about it and ask for him to help us be patient.  

When we see someting that needs to be done and we are blocked from doing it, we can become very frustrated and angry.  David learned that anger and frustration gets nowhere.  So...back we go to God, asking for patience and direction.  It's silly to look at other people who seem to be achieving their dreams and angrily beat our heads againt the wall, asking, "What about me?"  That achieves nothing but hurt for ouselves.  

Often it is not outright crooks or very evil people (in our eyes) who frustrate our plans.  It may simply be people who have different ideas about how things should happen, or who, for reasons of their own continually 'put spanners in the wheel'.  We need to wait in confidence that God will achieve his plans.  
Any schemes we might have to try to force our ideas and plans (even if we believe they are also God's) can just lengthen the waiting period and delay the time when God will get things going.

Quest Study Bible note, p 760. Land in the Old Testament symbolized more than just a piece of property.  It often represented the blessing and presence of God.  God's promise is that one day the tables will be turned: those who are well off may not be in the future;  those who suffer will one day be comforted.  Ultimately the righteous will be rewarded and the wicked will be brought to ruin.  Jesus made the same point in saying that the meek will inherit the earth (Matthew 5: 5)