When thou goest about to pray, first make and frame betwixt thee and God in thy mind a full purpose and intention in the beginning to serve Him, then with all the powers of thy soul by thy present prayer, and then begin and do as well as thou canst. Though thou be never so much letted contrary to thy former purpose, be not afraid, neither be angry at thyself, nor impatient against God, because He giveth thee not the savour and spiritual sweetness in devotion as thou thinkest He giveth to others. But see therein thy own feebleness and bear it patiently, deeming it to be (as it is) feeble and of no worth in thy own sight, with humility of spirit; trusting also firmly in the mercy of our Lord, that he will make it good and profitable to thee, more than thou imaginest or feelest. For know thou well that thou art excused of thy duty, and thou shalt be rewarded for this (as well as for any other good work done in charity), though thy mind and intention may be not so fully set upon it as thou wishest. (John Climacus)

We begin with purpose and intention. John may be referencing τέλος (telos) and ἔννοια (ennoia).

What is my function, goal, and end in serving God? This is my telos.

What is my act of thinking, the conception spawned by thinking, the notion that emerges from feeling? This is my ennoia.

Can I ever know more than ennoia? I can bring intention to my life. But can I know purpose?

Love God with your whole heart, soul, and mind, and your neighbor as yourself.