What should I do in trying to witness to an older friend?

Gerry, a friend of mine from work has weighed heavy on my दिल now for awhile due to spiritual concerns. I do not know of his past life true, but some things that I have gotten to know about him make me even और concerned for him. I have put Gerry in prayer lists, दिया him religious cards, and been polite and descent towards him, as a Christian should but know there must be alot deeper things needed to be done. The problem is that he is many years older than I am and the option for inviting him somewhere या anything of that matter will या may seem awkward and wrong...maybe have some help from an older church member या something? I am stuck, I want so much for him to find salvation, he is such a sweet person and basically, I am afraid for him...can anyone help?? please??? :(