Why do Christians today have a hard time accepting this wonderful invitation?
We do not see Jesus as our Life, our Savior in every way, for every need, but rather as an initial Helper, whom we then run to once in a while for additional help.
Jesus is our Life, and He came that we would have His life:
"But he shall receive an hundredfold now in this time, houses, and brethren, and sisters, and mothers, and children, and lands, with persecutions; and in the world to come eternal life." (Mark 10: 30)
"For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life." (John 3: 16)
"The thief cometh not, but for to steal, and to kill, and to destroy: I am come that they might have life, and that they might have it more abundantly." (John 10: 10)
"If ye then be risen with Christ, seek those things which are above, where Christ sitteth on the right hand of God. 2Set your affection on things above, not on things on the earth. 3For ye are dead, and your life is hid with Christ in God. 4When Christ,who is our life, shall appear, then shall ye also appear with him in glory." (Colossians 3: 1-4)
So, if He is our life, we need to rest in Him, and Let Him work.
In fact, He is already working, laboring within us!
"But by the grace of God I am what I am: and his grace which was bestowed upon me was not in vain; but I laboured more abundantly than they all: yet not I, but the grace of God which was with me." (1 Corinthians 15: 10)
"Wherefore, my beloved, as ye have always obeyed, not as in my presence only, but now much more in my absence, work out your own salvation with fear and trembling. 13For it is God which worketh in you both to will and to do of his good pleasure." (Philippians 2: 12-13)
"Whereunto I also labour, striving according to his working, which worketh in me mightily." (Colossians 1: 29)
Jesus labors in us, and we allow Him to work.