But I [am] poor and needy
 In ( Psalms 40:17 ) it follows, yet "the Lord thinketh on me"; instead of which it is here, (See Gill on Psalms 40:17); 
 make haste unto me, O God;
 which repeats for sense the same petition as in ( Psalms 71:1 ) ; 
 thou [art] my help and my deliverer; O Lord, make no tarrying;
 in ( Psalms 40:17 ) it is, "O my God".